Process for forming deposited film

ABSTRACT

A process for forming a deposited film comprises introducing into a film forming space housing a substrate therein an active species (A) formed by decomposition of a compound containing germanium and a halogen and an active species (B) formed from a chemical substance for film formation which is reactive with said active species (A) separately from each other, then irradiating them with light energy and thereby allowing both the species to react with each other thereby to form a deposited film on the substrate.

This application is a continuation of application Ser. No. 939,229 filedDec. 8, 1986 which is a continuation of application Ser. No. 829,928filed Feb. 18, 1986 both now abandoned.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a process suitable for forming a depositedfilm, in particular a functional film, above all an amorphous orcrystalline deposited film to be used for semiconductor devices,photosensitive devices for electrophotography, line sensors for imageinput, image pick-up devices, photovoltaic devices, etc.

2. Description of the Prior Art

For example, for formation of an amorphous silicon film, an amorphousgermanium film, etc. the vacuum deposition method, the plasma CVDmethod, the CVD method, the reactive sputtering method, the ion platingmethod, the optical CVD method or the like have been attempted to beutilized, and, in general, the plasma CVD method has widely been usedand industrialized.

However, for the deposited film composed of amorphous silicon, amorphousgermanium, etc. there is room for further improvement of overallcharacteristics, that is, electrical or optical characteristic, fatiguecharacteristic in repeated use, characteristic for use environment,productivity, mass productivity including uniformity, andreproducibility and the like.

The reaction process in formation of an amorphous silicon depositedfilm, an amorphous germanium deposited film, etc. according to theplasma CVD method generalized in the prior art is considerablycomplicated as compared with the conventional CVD method and not a fewambiguities existed in its reaction mechanism. Also, there are involveda large number of parameters for formation of such a deposited film(e.g. substrate temperature, flow rates and ratios of gases introduced,pressure during film formation, high frequency power, electrodestructure, structure of reaction vessel, gas discharging speed, plasmageneration system, etc.), and the nature of formed plasma depends onsuch a large number of parameters and sometimes becomes unstable. Thisoften gives markedly bad influences of the deposited film formed.Besides, the parameters associated with an apparatus must be chosen foreach apparatus, and it has been difficult under the present situation tostandardize the production conditions. On the other hand, for forming anamorphous silicon film, an amorphous germanium film, etc. havingsatisfactory electrical, optical, photoconductive or mechanicalcharacteristics for respective uses, it has been deemed best to formsuch a film according to the plasma CVD method under the presentsituation.

However, in some applied uses of the deposited film, it is required tosufficiently accomplish enlargement of film area, uniformization of filmthickness and film quality, etc. and also to perform a mass productionwith reproducibility by high speed film formation. Thus, in formation ofamorphous silicon deposited film, amorphous germanium deposited films,etc. according to the plasma CVD method, enormous investment for massproduction equipment is necessary, and operating conditions for massproduction is complicated and it makes the tolerance narrower and makesthe regulation of apparatuses delicate. These problems have been pointedout to be improved in the future. On the other hand, in the prior artusing the conventional CVD method, high temperature is required and nodeposited film having practical characteristics could be obtained.

As described above, in formation of amorphous silicon films, amorphousgermanium films, etc., it has earnestly been desired to develop aformation process which can perform mass production by means of a lowcost apparatus while maintaining practical characteristics anduniformity. These discussions may also be applicable to other functionalfilms such as silicon nitride films, silicon carbide films, siliconoxide films, germanium nitride films, germanium carbide films, germaniumoxide films, etc.

SUMMARY OF THE INVENTION

The present invention provides a novel process for formation of adeposited film which removes the drawbacks of the plasma CVD method asdescribed above and does not use conventional film forming methods ofthe prior art.

An object of the present invention is to provide a process for forming adeposited film which is suitable for enlargement of the film and caneasily accomplish improvement of productivity and mass production of thefilm, while attempting to improve the characteristics of the filmformed, the film forming speed and reproducibility and also touniformize film quality.

According to the present invention, there is provided a process forforming a deposited film, which comprises introducing into a filmforming space housing a substrate therein an active species (A) formedby decomposition of a compound containing germanium and a halogen and anactive species (B) formed from a chemical substance for film formationwhich is reactive with said active species (A) separately from eachother, then irradiating them with light energy and thereby allowing boththe species to react with each other to form a deposited film on thesubstrate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic sectional view for illustration of a constructionexample of the image forming member for electrophotography produced byuse of the process of the present invention;

FIG. 2 is a schematic sectional view for illustration of a constructionexample of a PIN type diode produced by use of the process of thepresent invention; and

FIG. 3 and FIG. 4 are schematic diagrams for illustration of theconstitutions of the devices for practicing the process of the presentinvention employed in respective examples.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the process of the present invention, since gases for film formationare excited and reacted by the use of light energy, i.e. in the presenceof both active species (A) formed by decomposition of compoundscontaining germanium and halogens and active species (B) formed fromchemical substances for film formation light energy acts on them tocause, accelerate or amplify chemical mutual reactions, deposited filmsthus formed are free from bad influence by etching action or otheractions such as abnormal discharging action, etc.

Also, according to the present invention, by controlling the atmospheretemperature in the film forming space and the substrate temperature asdesired, the CVD process can be made more stable.

Moreover, since light energy can be applied equally or selectively torespective active species reaching the proximity of a substrate, oruniformly or to a particular portion of a substrate by means of anappropriate optical system to form a deposited film on the whole surfaceor a desired portion thereof, and also can be directed only to a givenfigure portion to form a deposited film thereat, light energy isadvantageously employed as an excitation energy.

One of the points in which the process of the present invention isdifferent from the CVD process of the prior art is to use active speciesobtained by being previously activated in a space different from thefilm forming space (hereinafter referred to as activation space). Bydoing so, the film forming speed can be dramatically increased ascompared with the CVD method of the prior art. In addition, thesubstrate temperature during film formation can be lowered to a greatextent, whereby deposited films with stable film quality can be providedcommercially in a large amount and yet at low cost.

The term active species (A) as herein mentioned refers to those havingthe action of promoting formation of deposited films by causing chemicalmutual actions with the active species (B) formed from a chemicalsubstance for film formation, thereby imparting energy or causingchemical reactions to occur. Thus, the active species (A) may eithercontain the constituent elements which become the constituent elementsconstituting the deposited film to be formed or contain no suchconstituent element.

In the present invention, the active species (A) from the activationspace (A) should preferably be selected for use, as desired, from thosehaving a life of 0.1 sec. or longer, more preferably 1 sec. or longer,optimally 10 sec. or longer, from the standpoint of productivity andeasiness in handling.

In the present invention, as the compound containing germanium and ahalogen to be introduced into the activation space (A), there may beemployed, for example, chain or cyclic hydrogenated germaniums of whichhydrogen atoms are partially or wholly substituted with halogen atoms,typically chain germanium halides represented by Ge_(u) Y_(2u+2) (u isan integer of 1 or more, and Y is at least one element selected from F,Cl, Br and I); cyclic carbon halides represented by Ge_(v) Y_(2v) (v isan integer of 3 or more, and Y has the same meaning as defined above),and chain or cyclic compounds represented by Ge_(u) H_(x) Y_(y) (u and Yhave the same meanings as defined above, x+Y=2u or 2u+2).

Specific examples may include gaseous or readily gasifiable compoundssuch as GeF₄, (GeF₂)₅, (GeF₂)₆, (GeF₂)₄, Ge₂ F₆, Ge₃ F₈, GeHF₃, GeH₂ F₂,GeCl₄, (GeCl₂)₅, GeBr₄, (GeBr₂)₅, Ge₂ Cl₆, Ge₂ Br₆, GeHCl₃, GeHBr₃,GeHI₃, Ge₂ Cl₃ F₃ and the like.

Also, in the present invention, in addition to the active species (A)formed by decomposition of the compound containing germanium and ahalogen, it is also possible to use an active species (SX) formed bydecomposition of a compound containing silicon and a halogen and/or anactive species (CX) formed by decomposition of a compound containingcarbon and a halogen in combination.

As the compound containing silicon and a halogen, there may be employed,for example, chain or cyclic hydrogenated silicon of which hydrogenatoms are partially or wholly substituted with halogen atoms, typicallychain silicon halides represented by Si_(u) Z_(2u+2) (u is an integer of1 or more, Z is at least one element selected from F, Cl, Br and I),cyclic silicon halides represented by Si_(v) Z_(2v) (v is an integer of3 or more, and Z has the same meaning as defined above), and chain orcyclic compounds represented by Si_(u) H_(x) Z_(y) (u and Z have thesame meanings as defined above, x+y=2u or 2u+2).

Specific examples may include gaseous or readily gasifiable compoundssuch as SiF₄, (SiF₂)₅, (SiF₂)₆, (SiF₂)₄, Si₂ F₆, Si₃ F₈, SiHF₃, SiH₂ F₂,SiCl₄, (SiCl₂)₅, SiBr₄, (SiBr₂)₅, Si₂ Cl₆, Si₂ Br₆, SiHCl₃, SiHBr₃,SiHI₃, Si₂ Cl₃ F₃, and the like.

These compounds containing silicon and a halogen may be used alone or asa combination of two or more compounds.

As the compound containing carbon and a halogen to be introduced intothe activation space (A), there may be employed, for example, chain orcyclic hydrocarbons of which hydrogen atoms are partially or whollysubstituted with halogen atoms, typically chain carbon halidesrepresented by C_(u) Y_(2u+2) (u is an integer of 1 or more, Y is atleast one element selected from F, Cl, Br and I) cyclic carbon halidesrepresented by C_(v) Y_(2v) (v is an integer of 3 or more, and Y has thesame meaning as defined above), and chain or cyclic compoundsrepresented by C_(u) H_(x) Y_(y) (u and Y have the same meanings asdefined above, x+y=2u or 2u+2).

Specific examples may include gaseous or readily gasifiable compoundssuch as CF₄, (CF₂)₅, (CF₂)₆, (CF₂)₄, C₂ F₆, C₃ F₈, CHF₃, CH₂ F₂, CCl₄,(CCl₂)₅, CBr₄, (CBr₂)₅, C₂ Cl₆, C₂ Br₆, CHCl₃, CHBr₃, CHI₃, C₂ Cl₃ F₃,and the like.

These compounds containing carbon and a halogen may be used alone or asa combination of two or more compounds.

For formation of the active species (A), in addition to the abovecompound containing germanium and a halogen (and the compound containingcarbon and a halogen or the compound containing silicon and a halogen),other germanium compounds such as single substance of germanium, etc.,hydrogen or halogen compounds (e.g., F₂ gas, Cl₂ gas, gasified Br₂, I₂,etc.) may be used in combination.

Chemical substances for film formation to be used in the presentinvention are supplied with activation energy in the activation space(B) to be activated, then introduced to the film forming space, thereinexcited by the action of light energy, and react mutually with theforegoing active species (A) simultaneously introduced from theactivation space (A), thus resulting the easy formation of a desiredfilm on a desired substrate.

In other words, as the chemical substance for film formation for formingthe active species (B) used in the present invention, there may beincluded those containing the constituent elements which become theconstituent elements constituting the deposited film to be formed andfunctioning as a starting material for formation of the deposited filmor those not containing the constituent elements which become theconstituent elements constituting the deposited film to be formed andcapable of being considered to merely contribute to film formation. Thecompounds functioning as a starting material for formation of thedeposited film and the compounds contributing the film formation may beused in combination.

The chemical substance for film formation to be used in the presentinvention may preferably be already gaseous or made gaseous beforeintroduction into activation space (B). For example, when a liquidcompound is used, a suitable gasfying device can be connected to thesource for supplying the compound, and the compound can be gasifiedbefore introduction into the activation space (B).

In the activation space (B) to be used in the process of the presentinvention, as the above chemical substance for film formation forforming active species (B), hydrogen gas and/or halogen compounds (e.g.F₂ gas, Cl₂ gas, gasified Br₂, I₂, etc.) may be advantageously employed.Also, in addition to these chemical substances for film formation, inertgases such as helium, argon, neon, etc. may be used. When a plurality ofthese chemical substances for film formation are to be employed, theycan be previously mixed before introduction into the activation space(B), or alternatively these chemical substances can individually besupplied from feeding sources independent of each other to be introducedinto the activation space (B), or into independent respective activationspaces to be individually activated therein.

In the activation space (B) to be used in the process of the presentinvention, as the above chemical substance for film formation forforming active species (B), there may also be advantageously employedsilicon containing compounds, carbon containing compounds, germaniumcontaining compounds, oxygen containing compounds and nitrogencontaining compounds.

As the silicon containing compound, there may be employed unsubstitutedor substituted silanes having hydrogen, halogen and hydrocarbon groupsbonded to silicon. Above all, chain or cyclic silane compounds and thosechain and cyclic silane compounds of which hydrogen atoms aresubstituted partially or wholly with halogen atoms are preferred.

Specifically, there may be included, for example, straight chain silanecompounds represented by Si_(p) H_(2p+2) (p is an integer of 1 or more,preferably 1 to 15, more preferably 1 to 10) such as SiH₄, Si₂ H₆, Si₃H₈, Si₄ H₁₀, Si₅ H₁₂, Si₆ H₁₄, etc. which may be substituted withhalogen; branched chain silane compounds represented by Si_(p) H_(2p+2)(p has the same meaning as mentioned above) such as SiH₃ SiH(SiH₃)SiH₃,SiH₃ SiH(SiH₃)Si₃ H₇, Si₂ H₅ SiH(SiH₃)Si₂ H₅, etc. which may besubstituted with halogen; and cyclic silane compounds represented bySi_(q) H_(2q) (q is an integer of 3 or more, preferably 3 to 6) such asSi₃ H₆, Si₄ H₈, Si₅ H₁₀, Si₆ H₁₂, etc. which may be substituted withother cyclic silanyl groups and/or chain silanyl groups. Examples of theabove silane compounds in which a part or all of the hydrogen atoms aresubstituted with halogen atoms may include halo-substituted chain orcyclic silane compounds represented by Si_(r) H_(s) X_(t) (X is ahalogen atom, r is an integer of 1 or more, preferably 1 to 10, morepreferably 3 to 7, s+t=2r+2 or 2r) such as SiH₃ F, SiH₃ Cl, SiH₂ Br,SiH₃ I, etc. These compounds may be used either alone or as acombination of two or more compounds.

In the above case, in addition to the silicon containing compounds forfilm formation, it is possible to introduce one or more kinds of theaforesaid hydrogen gas, halogen compounds (e.g. F₂ gas, Cl₂ gas,gasified Br₂, I₂, etc.) and inert gases such as helium, argon, neon,etc. into the activation space (B). When a plurality of these chemicalsubstances for film formation are to be employed, they can be previouslymixed before introduction into the activation space (B), oralternatively these starting gases can individually be supplied fromfeeding sources independent of each other to be introduced into theactivation space (B), or into independent respective activation spacesto be individually activated therein.

As the carbon containing compound, there may be employed preferablygaseous or readily gasifiable compounds selected from chain or cyclicsaturated or unsaturated hydrocarbon compounds, organic compoundscontaining carbon and hydrogen as main constituent atoms andadditionally containing at least one of halogen, sulfur, etc. asconstituent atoms, and organic silicon compounds containing hydrocarbongroups as constituent components or having silicon-carbon bonds.

Among them, as hydrocarbon compounds, there may be enumerated saturatedhydrocarbons having 1 to 5 carbon atoms, ethylenic hydrocarbons having 2to 5 carbon atoms, acetylenic hydrocarbons having 2 to 4 carbon atoms,including specifically, as saturated hydrocarbons, methane (CH₄), ethane(C₂ H₆), propane (C₃ H₈), n-butane (n-C₄ H₁₀), pentane (C₅ H₁₂); asethylenic hydrocarbons, ethylene (C₂ H₄), propylene (C₃ H₆), butene-1(C₄ H₈), butene-2(C₄ H₈), isobutylene (C₄ H₈), pentene (C₅ H₁₀); asacetylenic hydrocarbons, acetylene (C₂ H₂), methylacetylene (C₃ H₄),butyne (C₄ H₆), etc.

As halo-substituted hydrocarbon compounds, there may be enumeratedcompounds in which at least one of hydrogen atoms which are constituentsof the above hydrocarbon compounds are substituted with F, Cl, Br or I,particularly those in which hydrogen is substituted with F or Cl, aseffective ones.

The halogens substituted for hydrogen may be either one kind or two ormore kinds in one compound.

As organic silicon compounds to be used in the present invention mayinclude organosilanes and organohalogenosilanes.

Organosilanes and organohalogenosilanes are compounds represented,respectively, by the general formulae:

    R.sub.n SiH.sub.4-n and R.sub.m SiX.sub.4-m

wherein R is alkyl or aryl; X is F, Cl, Br or I; n=1,2,3 or 4; and m=1,2or 3, including typically alkylsilanes, arylsilanes,alkylhalogenosilanes, and arylhalogenosilanes.

Specific example of organochlorosilanes include

trichloromethylsilane--CH₃ SiCl₃,

dichlorodimethylsilane--(CH₃)₂ SiCl₂,

chlorotrimethylsilane--(CH₃)₃ SiCl,

trichloroethylsilane--C₂ H₅ SiCl₃ and

dichlorodiethylsilane--(C₂ H₅)₂ SiCl₂.

Specific examples of organochlorofluorosilanes include

chlorodifluoromethylsilane--CH₃ SiF₂ Cl,

dichlorofuloromethylsilane--CH₃ SiFCl₂,

chlorofulorodimethylsilane--(CH₃)₂ SiFCl,

chloroethyldifluorosilane--(C₅ H₅)SiF₂ Cl,

dichloroethylfluorosilane--C₂ H₅ SiFCl₂,

chlorodifluoropropylsilane--C₃ H₇ SiF₂ Cl and

dichlorofluoropropylsilane--C₃ H₇ SiFCl₂.

Specific examples of organosilanes include

tetramethylsilane--(CH₃)₄ Si,

ethyltrimethylsilane--(CH₃)₃ SiC₂ H₅,

trimethylpropylsilane--(CH₃)₃ SiC₃ H₇,

triethylmethylsilane--CH₃ Si(C₂ H₅)₃ and

tetraethylsilane--(C₂ H₅)₄ Si.

Specific examples of organohydrogenosilanes include

methylsilane--CH₃ SiH₃,

dimethylsilane--(CH₃)₂ SiH₂,

trimethylsilane--(CH₃)₃ SiH,

diethylsilane--(C₂ H₅)₂ SiH₂,

triethylsilane--(C₂ H₅)₃ SiH,

tripropylsilane--(C₃ H₇)₃ SiH and

diphenylsilane--(C₆ H₅)₂ SiH₂.

Specific examples of organofluorosilanes include

trifluoromethylsilane--CH₃ SiF₃,

difluorodimethylsilane--(CH₃)₂ SiF₂,

fluorotrimethylsilane--(CH₃)₃ SiF,

ethyltrifluorosilane--C₂ H₅ SiF₃,

diethyldifluorosilane--(C₂ H₅)₂ SiF₂,

triethylfulorosilane--(C₂ H₅)₃ SiF and

trifluoropropylsilane--(C₃ H₇)SiF₃.

Specific examples of organobromosilanes include

bromotrimethylsilane--(CH₃)₃ SiBr and

dibromodimethylsilane--(CH₃)₂ SiBr₂.

In addition, it is also possible to use organopolysilanes, for example,organodisilanes such as

hexamethyldisilane--[(CH₃)₃ Si]₂ and

hexapropyldisilane--[(C₃ H₇)₃ Si]₂.

These carbon containing compounds may be used either alone or as acombination of two or more compounds.

In the above case, in addition to the carbon containing compounds, oneor more kinds of hydrogen, halogen compounds (e.g. F₂ gas, Cl₂ gas,gasified Br₂, I₂, etc.), inert gases such as helium, neon, argon, etc.and the aforesaid silicon compounds may be introduced into theactivation space (B). When a plurality of these chemical substances forfilm formation are to be employed, they can be previously mixed in agaseous state before introduction into the activation space (B), oralternatively these starting gases for film formation can individuallybe supplied from feeding sources independent of each other to beintroduced into the activation space (B), or into independent respectiveactivation spaces to be individually activated therein.

As the germanium containing compounds, there may be employed inorganicor organic germanium containing compounds having hydrogen, halogens orhydrocarbon groups bonded to germanium, as exemplified by organicgermanium compounds such as chain or cyclic hydrogenated germaniumrepresented by Ge_(a) H_(b) (a is an integer of 1 or more, b=2a+2 or2a); polymers of the hydrogenated germanium; compounds in which a partor all of the hydrogen atoms in the above hydrogenated germanium aresubstituted with halogen atoms; compounds in which a part or all of thehydrogen atoms in the above hydrogenated germanium compounds aresubstituted with organic groups such as alkyl groups, aryl groups, etc.or, if desired, halogen atoms; etc. and inorganic germanium compoundssuch as sulfide, imides, etc.

Specifically, there may be enumerated, for example, GeH₄, Ge₂ H₆, Ge₃H₈, n-Ge₄ H₁₀, tert-Ge₄ H₁₀, Ge₃ H₆, Ge₅ H₁₀, GeH₃ F, GeH₃ Cl, GeH₂ F₂,H₆ Ge₆ F₆, Ge(CH₃)₄, Ge(C₂ H₅)₄, CH₃ GeH₃, (CH₃)₂ GeH, (CH₃)₃ GeH, (C₂H₅)₂ GeH₂, Ge(C₆ H₅)₄, Ge(CH₃)₂ F₂, GeF₂, GeF₄, GeS, Ge₃ N₄, Ge(NH₂)₂,etc.

These germanium compounds may be used either alone or as a combinationof two or more compounds.

In the above case, in addition to the germanium containing compounds,one or more kinds of hydrogen, halogen compounds (e.g. F₂ gas, Cl₂ gas,gasified Br₂, I₂, etc.), inert gases such as helium, neon, argon, etc.and the aforesaid silicon containing compounds or carbon containing maybe introduced into the activation space (B). When a plurality of thesechemical substances for film formation are to be employed, they can bepreviously mixed in a gaseous state before introduction into theactivation space (B), or alternatively these starting gases for filmformation can individually be supplied from feeding sources independentof each other to be introduced into the activation space (B), or intoindependent respective activation spaces to be individually activatedtherein.

As the oxygen containing compound, there may be mentioned compoundsoxygen atoms and at least one atom other than oxygen as constituentatoms. Other atoms than oxygen as mentioned above include hydrogen (H),halogens (X=F, Cl, Br or I), sulfur (S), carbon (C), silicon (Si),germanium (Ge), phosphorus (P), boron (B), alkali metals, alkaline earthmetals, transition metals, etc. In addition, still other atoms, ofelements belonging to the respective groups in the periodic table, whichcan be bonded to an oxygen atom may be available.

For example, as compounds containing O and H, there may be enumerated H₂O, H₂ O₂, etc.; as compounds containing O and S, oxides such as SO₂,SO₃, etc.; as compounds containing O and C, oxides such as CO, CO₂,etc.; as compounds containing O and Si, siloxanes such as disiloxane (H₃SiOSiH₃), trisiloxane (H₃ SiOSiH₂ OSiH₃), etc., organoacetoxylilanessuch as diacetoxydimethylsilane (CH₃)₂ Si(OCOCH₃)₂,triacetoxymethylsilane CH₃ Si(OCOCH₃)₃, etc., alkylalkoxysilanes such asmethoxytrimethylsilane (CH₃)₃ SiOCH₃, dimethoxydimethylsilane (CH₃)₂Si(OCH₃)₂, trimethoxymethylsilane CH₃ Si(OCH₃)₃), etc.; organosilanolssuch as trimethylsilanol (CH₃)₃ SiOH, dimethylphenyl silanol (CH₃)₂ (C₆H₅)SiOH, diethylsilanediol (C₂ H₅)₂ Si(OH)₂, etc.; as comoundscontaining O and Ge, oxides, hydroxides of Ge, germanic acids, organicgermanium compounds such as H₃ GeOGeH₃, H₃ GeOGeH₂ OGeH₃, etc., but theoxygen containing compounds to be used in the present invention are notlimited to these compounds.

These oxygen containing compounds may be used either alone or as acombination of two or more compounds.

Also, it is possible to use gases other than these compounds such as O₂,O₃, etc.

In the above case, in addition to the oxygen containing compounds, it ispossible to introduce at least one of hydrogen, halogen compounds (e.g.F₂ gas, Cl₂ gas, gasified Br₂, I₂, etc.), inert gases such as helium,neon, argon, etc. and the aforesaid silicon containing compounds, carboncontaining compounds or germanium containing compounds into theactivation space (B). When a plurality of these chemical substances forfilm formation are to be employed, they can be previously mixed in agaseous state before introduction into the activation space (B), oralternatively these chamical substances for film formation canindividually be supplied from feeding sources independent of each otherto be introduced into the activation space (B), or into independentrespective activation spaces to be individually activated therein.

As the nitrogen containing compound, there may be included compoundscontaining nitrogen atoms and at least one atom other than nitrogen asconstituent atoms. Other atoms than nitrogen as mentioned above includehydrogen (H), halogens (X=F, Cl, Br or I), sulfur (S), carbon (C),oxygen (O), phosphorus (P), silicon (Si), germanium (Ge), boron (B),alkali metals, alkaline earth metals, transition metals, etc. Inaddition, still other atoms, of elements belonging to the respectivegroups in the periodic table, which can be bonded to an nitrogen atommay be available.

For example, as compounds containing N and H, there may be enumeratedNH₃, NH₄ N₃, N₂ H₅ N₃, H₂ NNH₂, primary to tertiary amines, halides ofthese amines, hydroxylamine, etc.; as compounds containing N and X, N₃X, N₂ X₂, NX₃, NOX, NO₂ X, NO₃ X₄, etc.; as compounds containing N andS, N₄ S₄, N₂ S₅, etc.; as compounds containing N and C, N(CH₃)₃, HCN andcyanides, HOCN and salts thereof, etc.; as compounds containing N and O,N₂ O, NO, NO₂, N₂ O₃, N₂ O₄, N₂ O₅, NO₃, etc; as compounds containing Nand P, P₃ N₅, P₂ N₃, PN, etc. In addition, there may also be employedorganosilazanes such as triethylsilazane (C₂ H₅)₃ SiNH₂,hexamethyldisilazane [(CH₃)₃ Si]₂ NH, hexaethyldisilazane [(C₂ H₅)₃ Si]₂NH, etc.; organosilicon isocyanates such as trimethylsilicon isocyanate(CH₃)₃ SiNCO, dimethylsilicon diisocyanate (CH₃)₂ Si(NCO)₂, etc.;organosilicon isothiocyanates such as trimethylsilicon isothiocyanate(CH₃)₃ SiNCS, etc. The nitrogen containing compound is not limited tothese compounds provided that the compound is fit for attaining theobject of the present invention.

These nitrogen containing compounds may be used either alone or as acombination of two or more compounds. Also, it is possible to use N₂gas.

In the above case, in addition to the nitrogen containing compounds, itis possible to introduce at least one of hydrogen, halogen compounds(e.g. F₂ gas, Cl₂ gas, gasified Br₂, I₂, etc.), inert gases such ashelium, neon, argon, etc. and the aforesaid silicon containingcompounds, carbon containing compounds, germanium containing compoundsor oxygen containing compounds into the activation space (B). When aplurality of these chemical substances for film formation are to beemployed, they can be previously mixed in a gaseous state beforeintroduction into the activation space (B), or alternatively thesechamical substances for film formation can individually be supplied fromfeeding sources independent of each other to be introduced into theactivation space (B), or into independent respective activation spacesto be individually activated therein.

In the present invention, the proportion in amount of the active species(A) to the active spacies (B) in the film forming space may suitably bedetermined depending on the depositing conditions, the kind of activatedspecies, etc., but may preferably be 10:1 to 1:10, more preferably 8:2to 4:6.

In the present invention, as the method for forming activate species (A)and (B) in the activation spaces (A) and (B), respectively, there may beemployed various activation energies such as electrical energiesincluding microwave, RF, low frequency, DC, etc., heat energiesincluding heater heating, IR-ray heating, etc., optical energies and thelike in view of the respective conditions and the device.

On the other hand, the deposited film formed according to the presentinvention can be doped with impurity elements during or after filmformation. As the impurity elements to be used, there may be employed,as p-type impurities, elements belonging to group III A of the periodictable such as B, Al, Ga, In, Tl, etc. and, as n-type imputities,elements belonging to group VA of the periodic table such as N, P, As,Sb, Bi, etc. as suitable ones. Particularly, B, Ga, P and Sb are mostpreferred. The doping amount of impurities may be determined suitablydepending on the desired electrical and optical characteristics.

Among compounds containing such impurity atoms as the components, it ispreferable to select a compound which is gaseous under normaltemperature and normal pressure, or gaseous at least under theactivating conditions, or a compound which can be readily gasified by asuitable gasifying device. Such compounds include PH₃, P₂ H₄, PF₃, PF₅,PCl₃, AsH₃, AsF₃, AsF₅, AsCl₃, SbH₃, SbF₅, BiH₃, BF₃, BCl₃, BBr₃, B₂ H₆,B₄ H₁₀, B₅ H₉, B₅ H₁₁, B₆ H₁₀, B₆ H₁₂, AlCl₃, etc.. The compoundscontaining impurity atoms may be used either alone or as a combinationof two or more compounds.

The substances for introduction of impurities may be introduced into theactivation space (A) and/or the activation space (B) together with therespective substances for formation of the active species (A) or theactive species (B) to be activated therein alternatively activated in athird activation space (C) separate from the activation space (A) andthe activation space (B). Also, the substances for introduction ofimpurities may be directly introduced into the film forming space ingaseous state.

The substance for introduction of impurity can be employed by selectingsuitably the activation energy as described above. The active speciesformed by activation of the substance for introduction of impurity (PN)may be previously mixed with the active species (A) and/or the activespecies (B) before introduction into the film forming space orindependently introduced into the film forming space.

Next, the present invention is described by referring to a typicalexample of the image forming member for electrophotography formed by theprocess of the present invention.

FIG. 1 is a schematic sectional view for illustration of theconstruction example of a typical photoconductive member obtained by thepresent invention.

Photoconductive member 10 shown in FIG. 1 is applicable as an imageforming member for electrophotography, and has a layer constitutionconsisting of intermediate layer 12 which may optionally be provided andphotosensitive layer 13 provided on substrate 11 as a photoconductivemember.

In preparation of the photoconductive member 10, the intermediate layer12 and/or the photosensitive member 13 can be prepared according to theprocess of the present invention. Further, when the photoconductivemember 10 has an protective layer provided for the purpose of protectingchemically or physically the surface of the photosensitive layer 13, ora lower barrier layer and/or an upper barrier layer provided forimproving dielectric strength, these layers can also be preparedaccording to the process of the present invention.

The substrate 11 may be either electroconductive or insulating. Aselectroconductive substrates, there may be mentioned metals such asNiCr, stainless steel, Al, Cr, Mo, Au, Ir, Nb, Ta, V, Ti, Pt, Pd, etc.or alloys thereof.

As insulating substrates, there may conventionally be used films orsheets of synthetic resins including polyesters, polyethylene,polycarbonates, cellulose acetate, polypropylene, polyvinyl chloride,polyvinylidene chloride, polystyrene, polyamides, etc.; glasses,ceramics, papers and so on. At least one side surface of thesesubstrates is preferably subjected to treatment for impartingelectroconductivity, and it is desirable to form other layers on theside at which said electroconductive treatment has been applied.

For example, electroconductive treatment of a glass can be effected byproviding a thin film of NiCr, Al, Cr, Mo, Au, Ir, Nb, Ta, V, Ti, Pt,Pd, In₂ O₃, SnO₂, ITO(In₂ O₃ +SnO₂), etc. thereon. Alternatively, asynthetic resin film such as a polyester film can be subjected to theelectroconducitve treatment on its surface by, for example, vacuum vapordeposition, electron-beam deposition or sputtering of a metral such asNiCr, Al, Ag, Pb, Zn, Ni, Au, Cr, Mo, Ir, Nb, Ta, V, Ti, Pt, etc. or bylaminating treatment with the said metal, thereby impartingelectroconductivity to the surface. The substrate may be shaped in anyform such as cylinders, belts, plates or others, and its form may bedetermined as desired. For example, when the photoconductive member 10in FIG. 1 is to be used as an image-forming member forelectrophotography, it may desirably be formed into an endless belt or acylinder for use in continuous high speed copying.

For example, the intermediate layer 12 has the function of impedingeffectively inflow of the carriers from the side of the substrate 11into the photosensitive layer 13 and permitting easy passage of thephotocarriers, formed in the photosensitive layer 13 by irradiation ofelectromagnetic wave and migrating toward the side of the substrate 11,from the side of the photosensitive layer 13 to the side of thesubstrate 11.

The intermediate layer 12 is composed of, for example, amorphousgermanium A-Ge(Si, H, X) containing germanium as a matrix and optionallysilicon (Si), hydrogen (H), halogens (X) or the like as constitutingatoms; amorphous germanium A-GeC(H, X, Si) containing germanium as amatrix and optionally silicon, hydrogen and/or halogens and furthercontaining carbon (C) as constituting atoms; amorphous silicon-germaniumA-SiGe (H, X) containing silicon and germanium as a matrix andoptionally hydrogen and/or halogens; amorphous silicon-germaniumA-SiGe(H, X, O) containing silicon and germanium as a matrix andoptionally hydrogen, halogens and/or oxygen (O) as constituting atoms;amorphous silicon-germanium A-SiGeN(H, X) containing silicon andgermanium as a matrix and optionally hydrogen and/or halogens andfurther containing nitrogen; or the like, and in addition may containp-type impurities such as boron (B) and n-type impurities such asphosphorus (P).

In the present invention, the content of substances controllingconductivity such as B, P, etc. contained in the intermediate layer 12may preferably be 0.001 to 5×10⁴ atomic ppm, more preferably 0.5 to1×10⁴ atomic ppm, optimally 1 to 5×10³ atomic ppm.

In the case of forming the intermediate layer 12, as starting materialsfor formation of the intermediate layer, active species (A) formed inactivation space (A) and active species (B) formed in activation space(B), optionally together with active species formed by activation ofhydrogen, halogens, inert gases, gases of silicon containing compounds,germanium containing compounds, carbon containing compounds, nitrogencontaining compounds, compounds containing impurity elements ascomponents, etc. may be introduced respectively and separately, or mixedtogether if desired, into the film forming space, in which the substrate11 is placed, and the intermediate layer 12 may be formed on thesubstrate 11 by causing a chemical reaction by the action of lightenergy.

The compound containing germanium and a halogen capable of formingactive species (A) by introduction into the activation space (A) duringformation of the intermediate layer 12 should desirably be selected fromthe aforesaid compounds, particularly those readily forming activespecies such as GeF₂ *. Similarly, as the compound containing siliconand halogen, it is desirable to select a compound from the compounds asmentioned above which can form readily active species such as SiF₂ *.Also, as the compound containing carbon and halogen, it is desirable toselect a compound from the compounds as mentioned above which can formreadily active species such as CF₂ *.

The intermediate layer 12 should have a layer thickness preferably 30 Åto 10 μ, more preferably 40 Å to 8 μ, optimally 50 Å to 5 μ.

The photosensitive layer 13 is constituted of, for example, an amorphousmaterial having a matrix of silicon atoms and optionally containinghydrogen atoms and/or halogen atoms (X) as constituent atoms(hereinafter referred to as "A-Si(H,X)"); an amorphous material having amatrix of silicon atoms and carbon atoms and optionally containinghydrogen atoms (H) and/or halogen atoms (X) (hereinafter referred to as"A-SiC(H,X); an amorphous material having a matrix of silicon atoms andoptionally containing hydrogen, halogen germanium, carbon, etc. asconstituent atoms (hereinafter referred to as A-Si(H, X, Ge, C); andamorphous material having a matrix of silicon atoms and germanium atomsoptionally containing hydrogen, halogen, carbon, etc. (A-SiGe(H,X,C))and the like, and has both functions of the charge generation functionof generating photocarriers by irradiation of laser beam and thefunction of transporting the charges.

The photosensitive layer 13 should have a layer thickness preferably of1 to 100μ, more preferably 1 to 80μ, optimally 2 to 50μ.

The photosensitive layer 13 is, for example, constituted of non-doped,Asi(H,X,Ge,C), Asi(H,X,Ge,C), A-Si(H,X,C), etc, but it may also containa substance for controlling conductivity characteristic with a polaritydifferent from the polarity of the substance for controllingconductivity characteristic contained in the intermediate layer 12 (e.g.n-type), if desired, or a substance of the same polarity may becontained therein, when the practical amount contained in theintermediate layer 12 is much, in an amount by far smaller than saidamount.

Formation of the photosensitive layer 13 may be performed, similarly asin the case of the intermediate layer 12, if it is to be preparedaccording to the process of the present invention, by introducing acompound containing germanium and halogen and, if desired, a compoundcontaining silicon and halogen into the activation space (A),decomposing these under a high temperature or exciting these through theapplication of discharging energy or light energy to form active species(A) and introducing said active species (A) into deposition space.

In the case of forming an intermediate layer 12 which is similar to orthe same in constituents as the photosensitive layer 13, up to formationof the photoconductive layer 13 can continuously be performed subsequentto formation of the intermediate layer 12.

Further, if desired, it is also possible to form an amorphous depositedfilm containing carbon and silicon as constituent atoms as the surfacelayer on the photosensitive layer and, in this case, film formation canalso be conducted according to the process of the present invention,similarly as the above intermediate layer and photosensitive layer.

FIG. 2 is a schematic illustraction showing a typical example of a PINtype diode device utilizing a deposited film doped with an impurityelement prepared by carrying out the process of the present invention.

In the drawing, 21 is a substrate, 22 and 27 are thin film electrodes,23 is a semiconductor film consisting of an n-type semiconductor layer24, an i-type semiconductor layer 25 and a p-type semiconductor layer26. 28 is a conductive wire to be connected to the external electricalcircuit.

These semiconductor layers are constructed of A-SiGe(H,X),A-SiGe(N,H,X), A-SiGe(O,H,X), A-SiGeC(H,X), A-Si(H,X), A-SiC(H,X) etc.and the present invention may be applicable for preparation for eitherone of these layers. Particularly, the semiconductor layer 26 can beprepared according to the process of the present invention to enhanceconvention efficiency.

As the substrate 21, there may be employed a conductive, semiconductiveor insulating substrate.

When the substrate 21 is conductive, the thin film electrode 22 may beomitted. As the semiconductive substrate, there may be employed, forexample, semiconductors such as Si, Ge, GaAs, ZnO, ZnS, etc.. Thin filmelectrodes 22, 27 can be obtained by forming thin films of NiCr, Al, Cr,Mo, Au, Ir, Nb, Ta, V, Ti, Pt, Pd, In₂ O₃, SnO₂, ITO(In₂ O₃ +SnO₂), etc.on the substrate 21 by treatment such as vacuum deposition, electronbeam vapor deposition, sputtering, etc.. The electrodes 22, 27 have afilm thickness preferably of 30 to 5×10⁴ Å, more preferably 100 to 5×10³Å.

For rendering the film constituting the semiconductor layer n-type orp-type, if desired, it can be formed by doping an n-type impurity or ap-type impurity or both impurities into the layer to be formed, whilecontrolling its amount, during layer formation.

For formation of n-type, i-type and p-type semiconductor layers, any oneor all of the layers can be formed by the process of the presentinvention, with the film formation being performed by introducing acompound containing germanium and halogen and, if desired, compoundscontaining silicon and halogen or compounds containing carbon andhalogen into the activation space (A) and decomposing these by theaction of an activation energy, whereby active species (A) of, forexample GeF₂ *, SiF₂ *, CF₂ *, etc. can be formed and introduced intothe film forming space. Also, separately, chemical substances for filmformation introduced into the activation space (B) optionally togetherwith an inert gas and a gas containing an impurity element as thecomponent, may be excited and decomposed, if desired, by respectiveactivation energies to form respective active species, which are thenseparately or in an appropriate mixture introduced into the film formingspace in which substrate 11 is placed. To these active speciesintroduced into the film forming space are applied light energy, andthereby chemical mutual reaction is caused, accelerated or amplified toform a deposited film on the substrate 11. The n-type and p-typesemiconductor layers should have a layer thickness preferably of 100 to10⁴ Å, more preferably 300 to 2000 Å. On the other hand, the i-typesemiconductor layer should preferably have a layer thickness preferablyof 500 to 10⁴ Å, more preferably 1000 to 10,000 Å.

The PIN type diode device shown in FIG. 2 is not necessarily required toprepare all the layers of P, I and N according to the process of thepresent invention, but the present invention can be carried out bypreparing at least one layer of P, I and N according to the process ofthe present invention.

Furthermore, the process of the present invention is preferablyapplicable to, other than the above embodiment, forming Si₃ N₄ insulatorfilms or partially nitrogenated Si films which are formed by the CVDmethod and constituting semiconductor devices such as IC's, transistors,diodes, photoelectric conversion devices and the like. Also, Si filmshaving a nitrogen concentration distribution in the layer thicknessdirection by controlling, for example, the time, the amount, etc. ofintroducing the nitrogen containing compound into the film formingspace. Otherwise, in addition to the nitrogen containing compound,hydrogen, halogens, the silicon containing compounds, the germaiumcontaining compounds, the carbon containing compounds, the oxygencontaining compounds, etc. may optionally used to form a film involvingbonds of N and H, X, Si, Ge, C, O, etc. as constituting units and havingdesired characteristics.

According to the process for forming a deposited film of the presentinvention, electrical, optical photoconductive and mechanicalcharactristics desired for the film to be formed can be improved, andyet a high speed film formation is possible without maintaining thesubstrate at a high temperature. Also, reproducibility in film formationcan be improved to enable improvement of the film quality anduniformization of the film quality, and the process is also advantageousin enlargement of area of the film and can easily accomplish improvementof productivity of films as well as bulk production of films. Further,since light energy is used as an excitation energy during filmformation, there can be exhibited such effects that film formation canbe effected also on a substrate which is poor in heat resistance orsusceptible to plasma etching action, and that the steps can beshortened by low temperature treatment.

The present invention is described in detail by referring to thefollowing Examples.

The present invention is described by referring to the followingExamples.

EXAMPLE 1

By means of the device as shown in FIG. 3, i-type, p-type and n-typeA-Ge (Si, H, X) deposited films were formed according to the operationsas described below.

In FIG. 3, 101 is a film forming chamber, and a desired substrate 103 isplaced on a substrate supporting stand 102 provided internally therein.

104 is a heater for heating the substrate, which heater 104 is used forheating treatment of the substrate 103 before the film forming treatmentor, after film formation, for annealing treatment for furtherimprovement of the characteristics of the film formed, and electricityis supplied through a conductive wire 105 to generate heat. Said heater104 is not driven during film formation.

106 through 109 are gas feeding systems, and they are providedcorresponding to the kinds of the gases for film formation, and inertgases optionally employed, and the gases of the compounds containingimpurity element as the component. When the gases employed are liquidunder the standard condition, a suitable gasifying device is provided.

In the drawing, symbols of the gas feeding sources 106 through 109affixed with a are branched pipes, those affixed with b flowmeters,those affixed with c pressure gauges for measuring the pressures on thehigher pressure side of the respective flowmeters, those affixed with dor e valves for controlling the flow rates of respective gases. 123 isthe activation chamber (B) for forming active species (B) and, aroundthe activation chamber 123, there is provided the microwave plasmagenerating device 122 for generating activation energy for formation ofactive species (B). The starting gas for formation of active species (B)supplied from the gas inflow pipe 110 is activated in the activationchamber (B), and the active species (B) formed is introduced through theinflow pipe 124 into the film forming chamber 101. 111 is a gas pressuregauge.

In the drawing, 112 shows an activation chamber (A), 113 an electricfurnace, 114 solid Ge particles and 115 a pipe for introduction of agaseous compound containing germanium and halogen as the startingmaterial for active species (A). The active species (A) formed in theactivation chamber 112 is introduced through the inflow pipe 116 intothe film forming chamber 101.

Also, when a film containing constituent atoms other than Ge such as Si,etc. is to be formed, an activation chamber (C) not shown similar to 112may be provided separately, and active species (SX) can be formed from acompound containing silicon and halogen and, for example, Si particles,etc. and introduced into the film forming chamber 101.

117 is a photoenergy generating device and, for example, a mercury lamp,a xenon lamp, carbon dioxide laser, argon ion laser, excimer laser, etc.may be employed.

The light 118 directed to the substrate 103 as a whole or the desiredportion of the substrate by use of a suitable optical system from thelight-energy generating device 117 is irradiated on the active speciesflowing in the direction of the arrowhead 119, and the irradiated activespecies undergo mutually chemical reaction thereby to form a depositedfilm of A-Ge (Si, H, X) on the whole or the desired portion of thesubstrate 103. In the drawing, 120 shows a gas discharging valve and 121a gas discharging pipe.

First, a polyethyleneterephthalate film 103 was placed on a supportingstand 102, and the film forming chamber 101 was evacuated by use of anevacuating device (not shown) to about 10⁻⁶ Torr. From a gas feedingsource 106, H₂ gas at 150 SCCM or a gas mixture thereof with PH₃ gas orB₂ H₆ gas (each being diluted to 1000 ppm with hydrogen gas) at 40 SCCMwas introduced into the activation chamber (B) 123 through the gasinflow pipe 110. H₂ gas, etc. introduced into the activation chamber (B)123 was activated by means of the microwave plasma generating device 122to be converted to activated hydrogen, etc., which were then introducedthrough the inflow pipe 124 into the film forming chamber 101.

On the other hand, the activation chamber (A) 102 was packed with solidGe particles 114, heated by the electric furnace 113, thereby meltingGe, whereinto GeF₄ was blown through the inflow pipe 115 from the bombnot shown, thus forming active species of GeF₂ *, which were thenintroduced into the film forming chamber 101 via the inflow pipe 116.Similarly, active species such as SiF₂ * was also introduced into thefilm forming chamber 101, if desired.

Thus, while maintaining the inner pressure in the film forming chamber101 at 0.4 Torr, light was irradiated from 1 kW Xe lamp vertically ontothe substrate to form a non-doped or doped A-Ge(Si,H,X) film (filmthickness 700 Å). The film forming speed was 21 Å/sec.

Subsequently, the non-doped or p-type A-Ge (Si,H,X) film sample obtainedwas placed in a vacuum deposition tank, wherein a comb-type Al-gapelectrode (length 250μ, width 5 mm) was formed under vacuum of 10⁻⁵Torr, and the dark electroconductivity θ_(d) was determined by measuringdark current at an applied voltage of 10 V for evaluation of the filmcharacteristics of the respective samples. The results are shown inTable 1A.

EXAMPLE 2

Except for using a H₂ /F₂ gas mixture in place of H₂ gas from the gasfeeding bomb 106, an A-Ge(Si,H,X) film was formed following the sameprocedure as in Example 1. The dark electroconductivities were measuredfor respective samples to obtain the results shown in Table 1A.

From Table 1A, it can be seen that A-Ge(Si,H, X) films excellent inelectrical characteristics can be obtained according to the presentinvention and also that A-Ge(Si,H,X) films in which B and P aresufficiently incorporated can be obtained.

EXAMPLE 3

By means of the device as shown in FIG. 4, a drum-shaped image formingmember for electrophotography with a layer constitution as shown in FIG.1 was prepared according to the operations as described below.

In FIG. 4, 201 shows a film forming chamber, 202 an activation chamber(A), 203 an electric furnace, 204 solid Ge particles, 205 an inflow pipefor the starting material of active species (A), 206 a pipe forintroducing active species, 207 a motor, 208 a heater which is usedsimilarly as 104 in FIG. 3, 209 and 210 are blowing pipes, 211 is analuminum cylinder substrate and 212 a gas discharging valve. 213 through216 are starting gas feeding sources similarly as 106 through 109 inFIG. 1, and 217-1 is a gas inflow pipe.

In the film forming chamber 201, the aluminum cylinder 211 is suspended,equipped internally thereof with the heater 208 so as to be rotatablewith the motor 207. 218 is a photoenergy generating device, and light isirradiated toward the desired portion of the aluminum cylinder 211.

Also, the activation chamber (A) 202 was packed with solid Ge particles204, heated by the electric furnace 203 to bring Ge into red hot state,whereinto GeF₄ was blown from the bomb not shown to form active speciesof GeF₂ *, which are then introduced into the film forming chamber 201via the inflow pipe 206.

Also, from the activation chamber (C) (not shown) having a structuresimilar to the activation chamber (A) 202, active species (SX) of SiF₂ *were formed from solid Si particles and SiF₄ and introduced into thefilm forming chamber 201.

The H₂ gas introduced was subjected to activation treatment such asplasma formation by means of the microwave plasma generating device 220in the activation chamber (B) 219 to become activated hydrogen, whichwas then introduced through the inflow pipe 217-2 into the film formingchamber 201. During this operation, if desired, impurity gases such asPH₃, B₂ H₆, etc. were also activated by introduction into the activationchamber (B) 219. While maintaining the pressure in the film formingchamber 201 at 1.0 Torr, light was irradiated from the 1 KW Xe lampvertically onto the circumferential surface of the aluminum cylinder211.

The aluminum cylinder 211 was rotated, while the discharging gas wasdischarged by controlling adequately the opening of the dischargingvalve 212. Thus, a photosensitive layer 13 was formed.

Also, the intermediate layer 12 was formed to a film thickness of 2000 Åby introducing a gas mixture of H₂ /B₂ H₆ (0.2% of B₂ H₆ in terms ofvol. %) through the inflow pipe 217-1 prior to formation of thephotosensitive layer 13.

COMPARATIVE EXAMPLE 1

According to the plasma CVD method in general, an image forming memberfor electrophotography having a layer constitution as shown in FIG. 1was formed by use of respective gases of GeF₄, SiF₄, H₂ and B₂ H₆ bymeans of the device having the same film forming chamber as the filmforming chamber 201 provided with a high frequency generator of 13.56MHz.

The conditions for preparation of the drumshaped image forming membersfor electrophotography obtained in Example 3 and comparative example 1and their performances are shown in Table 2A.

EXAMPLE 4

By means of the device as shown in FIG. 3, a PIN type diode as shown inFIG. 2 was prepared.

First, a polyethyleneterephthalate film 21 having ITO film 22 with athickness of 1000 Å vapor deposited thereon was placed on a supportingstand and, after reduced to a pressure of 10⁻⁶ Torr, active species GeF₂*, active species SiF₂ * formed similarly as in Example 1 was introducedinto the film forming chamber 101. H₂ gas, PH₃ gas (diluted to 1000 ppmwith hydrogen gas) were respectively introduced into the activationchamber (B) 123 to be activated. Subsequently, the activated gases wereintroduced through the inflow pipe 116 into the film forming chamber101. While maintaining the pressure in the film forming chamber 101 at0.1 Torr, photoirradiation was effected by a 1 KW Xe lamp to form an-type A-SiGe(H,X) film 24 (film thickness: 700 Å) doped with P.

Next, according to the same method as in formation of the n-typeA-SiGe(H,X) film except for stopping introduction of PH₃ gas andincreasing the value of SiF₂ */GeF₂ * to three-fold, a non-doped typeA-SiGe(H,X) film 25 (film thickness: 5000 Å) was formed.

Subsequently, by use of B₂ H₆ gas (diluted to 1000 ppm with hydrogengas) at 40 SCCM together with H₂ gas, following otherwise the samecondition as in the case of n-type, a p-type A-SiGe(H,X) film 26 (filmthickness: 700 Å) doped with b was formed. On this p-type film wasfurther formed by vapor deposition an aluminum electrode 27 with athickness of 1000 Å to provide a PIN type diode.

The diode element thus obtained (area 1 cm²) was subjected tomeasurement of I-V characteristic, and rectifying characteristic andphotoelectromotive effect were evaluated. The results are shown in Table3A.

Also, in photoirradiation characteristics, light was introduced from thesubstrate side, and a conversion efficiency of 8.0% or higher, an opencircuit voltage of 0.87 V and a short circuit current of 9.7 mA/cm² wereobtained at a photoirradiation intensity AMI (about 100 mW/cm²).

EXAMPLE 5

Except for using respective gases of H₂ and F₂ (H₂ /F₂ =15) in place ofthe H₂ gas from the inflow pipe 110, the same PIN type diode as inExample 4 was prepared. The rectifying characteristic andphotoelectromotive effect were evaluated and the results are shown inTable 3A.

From Table 3A, it can be seen that an amorphous simiconductor PIN typediode having better optical and electrical characteristics as comparedwith the prior art can be obtained according to the present invention.

EXAMPLE 6

By means of the device as shown in FIG. 3, i-type, p-type and n-typeA-GeSi(H,X) deposited films were formed according to the operations asdescribed below.

In FIG. 3, 101 is a film forming chamber, and a desired substrate 103 isplaced on a substrate supporting stand 102 provided internally therein.

104 is a heater for heating the substrate, which heater 104 is used forheating treatment of the substrate 104 before the film forming treatmentor, after film formation, for annealing treatment for furtherimprovement of the characteristics of the film formed, and electricityis supplied through a conductive wire 105 to generate heat. Said heater104 is not driven during film formation. The heated substratetemperature is not particularly limited, but it should preferably be 50°to 150° C., more preferably 100° to 150° C., in practicing the processof the present invention.

106 through 109 are gas feeding systems, and they are providedcorresponding to the kinds of gases of silicon-containing compounds, andhydrogen, halogen compounds, inert gases, gases of the compoundscontaining impurities as the component which are optionally employed.When these gases employed are liquid under the standard condition, asuitable gasifying device is provided.

In the drawing, symbols of the gas feeding sources 106 through 109affixed with a are branched pipes, those affixed with b flowmeters,those affixed with c pressure gauges for measuring the pressures on thehigher pressure side of the respective flowmeters, those affixed with dor e valves for controlling the flow rates of respective gases. 123 isthe activation chamber (B) for forming active species (B) and, aroundthe activation chamber 123, there is provided the microwave plasmagenerating device 122 for generating activation energy for formation ofactive species (B). The starting gas for formation of active species (B)supplied from the gas inflow pipe 110 is activated in the activationchamber (B), and the active species (B) formed is introduced through theinflow pipe 124 into the film forming chamber 101. 111 is a gas pressuregauge.

In the drawing, 112 shows an activation chamber (A), 113 an electricfurnace, 114 solid Ge particles and 115 a pipe for introduction of agaseous compound containing germanium and halogen as the startingmaterial for active species (A). The active species (A) formed in theactivation chamber 112 is introduced through the inflow pipe 116 intothe film forming chamber 101.

Also, when a film containing constituent atoms other than Ge such as Si,etc. is to be formed, an activation chamber (C) not shown similar to 112may be provided separately, and active species (SiX*) can be formed froma compound containing silicon and halogen and, for example, Siparticles, etc. and introduced into the film forming chamber 101.

117 is a photoenergy generating device and, for example, a mercury lamp,a xenon lamp, carbon dioxide laser, argon ion laser, excimer laser, etc.may be employed.

The light 118 directed to the substrate as a whole or the desiredportion of the substrate 103 by use of a suitable optical system fromthe light-energy generating device 117 is irradiated on the activespecies flowing in the direction of the arrowhead 119, and theirradiated active species undergo mutually chemical reaction thereby toform a deposited film of A-Si on the whole or the desired portion of thesubstrate 103. In the drawing, 120 shows a gas discharging valve and 121a gas discharging pipe.

First, a polyethyleneyterephthalate film 103 was placed on a supportingstand 102, and the film forming chamber 101 was evacuated by use of anevacuating device (not shown) to about 10⁻⁶ Torr. From a gas feedingsource 106, Si₅ H₁₀ at 150 SCCM or a gas mixture thereof with PH₃ gas orB₂ H₆ gas (each being diluted to 1000 ppm with hydrogen gas) at 40 SCCMwas introduced into the activation chamber (B) 123 through the gasinflow pipe 110. Si₅ H₁₀ gas, etc. introduced into the activationchamber (B) 123 was activated by means of the microwave plasmagenerating device 122 to be converted to activated hydrogen, activatedsilicon, etc., which were then introduced through the inflow pipe 124into the film forming chamber 101.

On the other hand, the activation chamber (A) 112 was packed with solidGe particles 114, heated by the electric furnace 113, thereby bringingGe into red hot state, whereinto GeF₄ was blown through the inflow pipe115 from the bomb not shown, thus forming active species of GeF₂ *,which were then introduced into the film forming chamber 101 via theinflow pipe 116. Similarly, active species such as SiF₂ *, etc. wereintroduced into the film forming chamber 101, if desired.

Thus, while maintaining the inner pressure in the film forming chamber101 at 0.3 Torr, a non-doped or doped A-Ge(Si,H,X) film (film thickness700 Å) was formed. The film forming speed was 23 Å/sec.

Subsequently, the non-doped or p-type A-Ge (Si,H,X) film sample wasplaced in a vacuum deposition tank, wherein a comb-type Al-gap electrode(length 250μ, width 5 mm) was formed under vacuum of 10⁻⁵ Torr, and thedark electroconductivity σ_(d) was determined by measuring dark currentat an application voltage of 10 V for evaluation of the filmcharacteristics of the respective samples. The results are shown inTable 1B.

EXAMPLES 7-9

Except for using straight chain SiH₄ branched Si₄ H₁₀ or H₆ Si₆ F₆ inplace of Si₅ H₁₀, A-SiGe(H,X) films were formed, following the sameprocedures as in Example 6. The dark electroconductivities were measuredto obtain the results shown in Table 1B.

From Table 1B, it can be seen that A-SiGe(H,X) films excellent inelectrical characteristics can be obtained according to the presentinvention and also that A-SiGe(H,X) films sufficiently doped can beobtained.

EXAMPLE 10

By means of the device as shown in FIG. 4, a drum-shaped image formingmember for electrophotography with a layer constitution as shown in FIG.1 was prepared according to the operations as described below.

In FIG. 4, 201 shows a film forming chamber, 202 an activation chamber(A), 203 an electric furnace, 204 solid Si particles, 205 an inflow pipefor the starting material of active species (A), 206 a pipe forintroducing active species, 207 a motor, 208 a heater which is usedsimilarly as 104 in FIG. 3, 209 and 210 are blowing pipes, 211 analuminum cylinder substrate and 212 a gas discharging valve. 213 through216 are starting gas feeding sources similarly as 106 through 109 inFIG. 1, and 217-1 is a gas introducing pipe.

In the film forming chamber 201, the aluminum cylinder 211 is suspended,equipped internally thereof with the heater 208 so as to be rotatablewith the motor 207. 218 is a photoenergy generating device, and light isirradiated toward the desired portion of the aluminum cylinder 211.

Also, the activation chamber (A) 202 was packed with solid Ge particles204, heated by the electric furnace 203 to bring Ge into red hot state,whereinto GeF₄ was blown into to form active species of GeF₂ *, whichwere then introduced into the film forming chamber 201 via the inflowpipe 206.

On the other hand, through the inflow pipe 217-1, Si₂ H₆ and H₂ gaseswere introduced into the activation chamber (B) 219. The Si₂ H₆ and H₂gases introduced were subjected to activation treatment such as plasmaformation by means of the microwave plasma generating device 220 in theactivation chamber (B) 219 to become activated hydrogen, which was thenintroduced through the inflow pipe 217-2 into the film forming chamber201. During this operation, if desired, impurity gases such as PH₃, B₂H₆, etc. were also activated by introduction into the activation chamber(B) 219.

While maintaining the pressure in the film forming chamber 201 at 1.0Torr, light was irradiated from the 1 KW Xe lamp vertically onto thecircumferential surface of the aluminum cylinder 211.

The aluminum cylinder 211 was rotated, while the discharging gas wasdischarged by controlling adequately the opening of the dischargingvalve 212. Thus, a photosensitive layer 13 is formed.

Also, the intermediate layer 12 was formed to a film thickness of 2000 Åby introducing a gas mixture of H₂ /B₂ H₆ (0.2% of B₂ H₆ in terms ofvol. %) through the inflow pipe 217-1.

COMPARATIVE EXAMPLE 2

According to the plasma CVD method of the prior art a drum-shaped imageforming member for electrophotography having a layer constitution asshown in FIG. 1 was formed by use of respective gases of Si₂ H₆, H₂ andB₂ H₆ by means of the device having the same film forming chamber as thefilm forming chamber 201 provided with a high frequency generator of13.56 MHz.

The conditions for preparation of the drum-shaped image forming membersfor electrophotography obtained in Example 10 and Comparative example 2and their performances are shown in Table 2B.

EXAMPLE 11

By means of the device as shown in FIG. 3, with the use of Si₃ H₆ as thesilicon-containing compound, a PIN type diode as shown in FIG. 2 wasprepared.

First, a polyethyleneterephthalate film 21 having ITO film 22 with athickness of 1000 Å vapor deposited thereon was placed on a supportingstand and, after reduced to a pressure of 10⁻⁶ Torr, active speciesGeF₂ * formed similarly as in Example 6 was respectively introduced intothe activation chamber (B) 123 to be activated. Also, from the inflowpipe 110, Si₃ H₆, H₂ and PH₃ gases (diluted to 1000 ppm with hydrogengas) were respectively introduced into the activation chamber (B) 123 tobe activated.

Next, the activated gases were introduced through the inflow pipe 116into the film forming chamber 101. While maintaining the pressure in thefilm forming chamber at 0.1 Torr, an n-type A-SiGe (H,X) film 24 (filmthickness 700 Å) doped with P was formed.

Subsequently, except for stopping introduction of PH₃, in the samemanner as in the case of n-type A-SiGe(H,X) film, a non-doped A-Sic(H,X)film 25 (film thickness: 5000 Å) was formed.

Next, by use of B₂ H₆ gas (diluted to 1000 ppm with hydrogen gas) at 40SCCM together with H₂ gas, following otherwise the same conditions as inthe case of the n-type, a p-type A-SiGe(H,X) film 26 (film thickness:700 Å) doped with B was formed. Further, on this p-type film was formedby vapor deposition an aluminum electrode 27 with a thickness of 1000 Åto provide a PIN type diode.

The diode element thus obtained (area 1 cm²) was subjected tomeasurement of I-V characteristic, and rectifying characteristic andphotoelectromotive effect were evaluated. The results are shown in Table3B.

Also, in photoirradiation characteristics, light was introduced from thesubstrate side, and a conversion efficiency of 7.8% or higher, an openend voltage of 0.91 V and a short circuit current of 10.2 mA/cm² wereobtained at a photoirradiation intensity AMI (about 100 mW/cm²).

EXAMPLES 12-14

Except for using straight chain Si₄ H₁₀, branched Si₄ H₁₀ or H₆ Si₆ F₆in place of Si₃ H₆, the same PIN type diode as in Example 11 wasprepared in the same manner as in Example 11. The rectifyingcharacteristic and photoelectromotive effect were evaluated and theresults are shown in Table 3B.

From Table 3B, it can be seen that an A-SiGe (H,X) semiconductor PINtype diode having better optical and electrical characteristics ascompared with the prior art can be obtained according to the presentinvention.

EXAMPLE 15

By means of the device as shown in FIG. 3, i-type, p-type and n-typeamorphous deposited films containing germanium and carbon were formedaccording to the operations as described below.

In FIG. 3, 101 is a film forming chamber, and a desired substrate 103 isplaced on a substrate supporting stand 102 provided internally therein.

104 is a heater for heating the substrate, which heater 104 is used forheating treatment of the substrate 103 before film formation or, afterfilm formation, for annealing treatment for further improvement of thecharacteristics of the film formed, and electricity is supplied througha conductive wire 105 to generate heat. Said heater 104 is not drivenduring film formation.

106 through 109 are gas feeding systems, and they are providedcorresponding to carbon-containing compounds, and the kinds of gasesoptionally employed such as hydrogen, halogen compounds, inert gases andcompounds containing impurity elements as the component. When thesegases employed are liquid under the standard condition, a suitablegasifying device is provided. In the drawing, symbols of the gas feedingsources 106 through 109 affixed with a are branched pipes, those affixedwith b flowmeters, those affixed with c pressure gauges for measuringthe pressures on the higher pressure side of the respective flowmeters,those affixed with d or e valves for controlling the flow rates ofrespective gases.

123 is the activation chamber (B) for forming active species (B) and,around the activation chamber 123, there is provided the microwaveplasma generating device 122 for generating activation energy forformation of active species (B). The starting gas for formation ofactive species (B) supplied from the gas inflow pipe 110 is activated inthe activation chamber (B), and the active species (B) formed isintroduced through the inflow pipe 124 into the film forming chamber101.

111 is a gas pressure gauge. In the drawing, 112 shows an activationchamber (A), 113 an electric furnace, 114 solid Ge particles and 115 apipe for introduction of a gaseous compound containing germanium andhalogen as the starting material for active species (A). The activespecies (A) formed in the activation chamber 112 is introduced throughthe inflow pipe 116 into the film forming chamber 101.

117 is a photoenergy generating device and, for example, a mercury lamp,a xenon lamp, carbon dioxide laser, argon ion laser, excimer laser, etc.may be employed.

The light 118 directed to the substrate as a whole or the desiredportion of the substrate 103 by use of a suitable optical system fromthe light-energy generating device 117 is irradiated on the activespecies flowing in the direction of the arrowhead 119, and theirradiated active species undergo mutually chemical reaction thereby toform a deposited film of A-GeC(H,X) on the whole or the desired portionof the substrate 103. In the drawing, 120 shows a gas discharging valveand 121 a gas discharging pipe.

First, a polyethyleneterephthalate film 103 was placed on a supportingstand 102, and the film forming chamber 101 was evacuated by use of anevacuating device to about 10⁻⁶ Torr. From a gas feeding bomb 106, CH₄gas or a gas mixture thereof with PH₃ gas or B₂ H₆ gas (each diluted to1000 ppm with hydrogen gas) at 40 SCCM was introduced into theactivation chamber (B) 123 through the gas inflow pipe 110.

CH₄ gas, etc. introduced into the activation chamber (B) 123 wasactivated by means of the microwave plasma generating device 122 to beconverted to hydrogenated carbon active species and active hydrogen,etc., which were then introduced through the inflow pipe 124 into thefilm forming chamber 101.

On the other hand, the activation chamber (A) 112 was packed with solidGE particles 114, heated by the electric furnace 113, thereby bringingGE into red hot state, whereinto GeF₄ was blown through the inflow pipe115 from the bomb not shown, thus forming active species of GeF₂ * asactive species (A), which were then introduced into the film formingchamber 101 via the inflow pipe 116.

While maintaining the inner pressure in the film forming chamber 101 at0.4 Torr, light was irradiated from 1 kW Xe lamp vertically onto thesubstrate to form a non-doped or doped amorphous film containinggermanium and carbon (film thickness 700 Å). The film forming speed was24 Å/sec.

Subsequently, the obtained non-doped or p-type amorphous deposited filmsample containing germanium and carbon was placed in a vacuum depositiontank, wherein a comb-type Al-gap electrode (length 250μ, width 5 mm) wasformed under vacuum of 10⁻⁵ Torr, and the dark electroconductivity σ_(d)was determined by measuring dark current at an application voltage of 10V for evaluation of the film characteristics of the respective samples.The results are shown in Table 1C.

EXAMPLES 16-18

Except for using straight C₂ H₆, C₂ H₄ or C₂ H₂ in place of CH₄,amorphous deposited films containing germanium and carbon were formed.The dark electroconductivities were measured to obtain the results shownin Table 1C.

From Table 1C, it can be seen that amorphous carbon films containinggermanium and carbon excellent in electrical characteristics can beobtained according to the present invention and also that amorphousfilms containing germanium and carbon sufficiently doped can beobtained.

EXAMPLE 19

By means of the device as shown in FIG. 4, a drum-shaped image formingmember for electrophotography with a layer constitution as shown in FIG.1 was prepared according to the operations as described below.

In FIG. 4, 201 shows a film forming chamber, 202 an activation chamber(A), 203 an electric furnace, 204 solid C particles, 205 an inflow pipefor the starting material of active species (A), 206 a pipe forintroducing active species, 207 a motor, 208 a heater which is usedsimilarly as 104 in FIG. 3, 209 and 210 are blowing pipes, 211 analuminum cylinder substrate and 212 a gas discharging valve. 213 through216 are starting gas feeding sources similarly as 106 through 109 inFIG. 1, and 217-1 is a gas introducing pipe.

In the film forming chamber 201, the aluminum cylinder 211 is suspended,equipped internally thereof with the heater 208 so as to be rotatablewith the motor 207.

218 is a photoenergy generating device, and light 219 is irradiatedtoward the desired portion of the aluminum cylinder 211.

Also, the activation chamber (A) 202 was packed with solid Ge particles204, heated by the electric furnace 203 to bring Ge into red hot state,whereinto GeF₄ was blown into to form active species of GeF₂ * as activespecies (B), which were then introduced into the film forming chamber201 via the inflow pipe 206.

On the other hand, through the inflow pipe 217-1, CH₄, Si₂ H₆ and H₂gases are introduced into the activation chamber (B) 219.

The CH₄, Si₂ H₆ and H₂ gases introduced were subjected to activationtreatment such as plasma formation by means of the microwave plasmagenerating device 220 in the activation chamber (B) 219 to becomehydrogenated carbon active species, hydrogenated silicon active speciesand activated hydrogen, which were then introduced through the inflowpipe 217-2 into the film forming chamber 201. During this operation, ifdesired, impurity gases such as PH₃, B₂ H₆, etc. were also activated byintroduction into the activation chamber (B) 220.

While maintaining the pressure in the film forming chamber 201 at 1.0Torr, light was irradiated from the 1 KW Xe lamp vertically onto thecircumferential surface of the aluminum cylinder 211.

The aluminum cylinder 211 was rotated, while the discharging gas wasdischarged by controlling adequately the opening of the dischargingvalve 212. Thus, a photosensitive layer 13 was formed.

Also, the intermediate layer 12 was formed to a film thickness of 2000 Åby introducing a gas mixture of H₂ /B₂ H₆ (0.2% of B₂ H₆ in terms ofvol. %) through the inflow pipe 217-1 prior to formation of thephotosensitive layer 13.

COMPARATIVE EXAMPLE 3

According to the plasma CVD method of the prior art an image formingmember for electrophotography having a layer constitution as shown inFIG. 1 was formed by use of respective gases of GeF₄, CH₄, Si₂ H₆, H₂and B₂ H₆ by means of the device having the same film forming chamber asthe film forming chamber 201 provided with a high frequency generator of13.56 MH_(z).

The conditions for preparation of the drum-shaped image forming membersfor electrophotography obtained in Example 19 and Comparative example 3and their performances are shown in Table 2C.

EXAMPLE 20

By means of the device as shown in FIG. 3, with the use of CH₄ as thecarbon compound, a PIN type diode as shown in FIG. 2 was prepared.

First, a polyethyleneterephthalate film 21 having ITO film 22 with athickness of 1000 Å vapor deposited thereon was placed on a supportingstand and, after reduced to a pressure of 10⁻⁶ Torr, active speciesGeF₂ * formed similarly as in Example 15 were introduced into the filmforming chamber 101. Also, from the inflow pipe 110, Si₂ H₆ and PH₃gases (diluted to 1000 ppm with hydrogen gas) were respectivelyintroduced into the activation chamber (B) 123 to be activated. Then,the activated gases were introduced through the inflow pipe 116 into thefilm forming chamber 101. While maintaining the pressure in the filmforming chamber at 0.1 Torr, an n-type a-SiGe(H,X) film 24 (filmthickness 700 Å) doped with P was formed by photoirradiation from a 1 KWXe lamp.

Next, according to the same method as in formation of the n-typea-SiGe(H,X) film except for stopping introduction of PH₃ gas, anon-doped type a-SiGe(H,X) film 25 (film thickness: 5000 Å) was formed.

Subsequently, by introducing CH₄ and B₂ H₆ gas (diluted to 1000 ppm withhydrogen gas) together with Si₃ H₆ gas, following otherwise the sameconditions as in the case of n-type, an A-SiGe(H,X) film 26 (filmthickness: 700 Å) doped with B was formed. Further, on this p-type filmwas formed by vapor deposition an aluminum electrode 27 with a thicknessof 1000 Å to provide a PIN type diode.

The diode element thus obtained (area 1 cm²) was subjected tomeasurement of I-V characteristic, and rectifying characteristic andphotoelectromotive effect were evaluated. The results are shown in Table3C.

Also, in photoirradiation characteristics, light was introduced from thesubstrate side, and a conversion efficiency of 8.3% or higher, an opencircuit voltage of 0.94 V and a short circuit current of 9.9 mA/cm² wereobtained at a photoirradiation intensity AMI (about 100 mW/cm²).

EXAMPLE 21-23

Except for using straight chain C₂ H₆, C₂ H₄ or C₂ H₂ in place of CH₄ asthe carbon compound, the same PIN type diode as in Example 20 wasprepared in the same manner as in Example 20. The rectifyingcharacteristic and photoelectromotive effect were evaluated and theresults are shown in Table 3C.

From Table 3C, it can be seen that carbon-containing A-SiGe(H,X) PINtype diode having better optical and electrical characteristics ascompared with the prior art can be obtained according to the presentinvention.

EXAMPLE 24

By means of the device as shown in FIG. 3, i-type, p-type and n-typea-Ge(H,X) deposited films were formed according to the operations asdescribed below.

In FIG. 3, 101 is a film forming chamber, and a desired substrate 103 isplaced on a substrate supporting stand 102 provided internally therein.

104 is a heater for heating the substrate, which heater 104 is used forheating treatment of the substrate 103 before the film forming treatmentor, after film formation, for annealing treatment for furtherimprovement of the characteristics of the film formed, and electricityis supplied through a conductive wire 105 to generate heat. During filmformation, said heater 104 is not driven.

106 through 109 are gas feeding systems, and they are providedcorresponding to germanium-containing compounds, and the kinds of gasesoptionally employed such as hydrogen, halogen compounds, inert gases,silicon-containing compounds, carbon-containing compounds and compoundscontaining impurity elements as the component. When these gases employedare liquid under the standard condition, a suitable gasifying device isprovided.

In the drawing, symbols of the gas feeding sources 106 through 109affixed with a are branched pipes, those affixed with b flowmeters,those affixed with c pressure gauses for measuring the pressures on thehigher pressure side of the respective flowmeters, those affixed with dor e valves for controlling the flow rates of respective gases. 123 isthe activation chamber (B) for forming active species (B) and, aroundthe activation chamber 123, there is provided the microwave plasmagenerating device 122 for generating activation energy for formation ofactive species (B). The starting gas for formation of active species (B)supplied from the gas inflow pipe 110 is activated in the activationchamber (B), and the active species (B) formed is introduced through theinflow pipe 124 into the film forming chamber 101. 111 is a gas pressuregauge.

In the drawing, 112 shows an activation chamber (A), 113 an electricfurnace, 114 solid Ge particles and 115 a pipe for introduction of agaseous compound containing germanium and halogen as the startingmaterial for active species (A). The active species (A) formed in theactivation chamber 112 is introduced through the inflow pipe 116 intothe film forming chamber 101.

117 is a photoenergy generating device and, for example, a mercury lamp,a xenon lamp, carbon dioxide laser, argon ion laser, excimer laser, etc.may be employed.

The light directed to the substrate as a whole or the desired portion ofthe substrate 103 by use of a suitable optical system from thelight-energy generating device 117 is irradiated on the active speciesflowing in the direction of the arrowhead 119, and the irradiated activespecies undergo mutually chemical reaction thereby to form a depositedfilm of a-Ge(H,X) on the whole or the desired portion of the substrate103. In the drawing, 120 shows a gas discharging valve and 121 a gasdischarging pipe.

First, a polyethyleneterephthalate film 103 was placed on a supportingstand 102, and the film forming chamber 101 was evacuated by use of anevacuating device to about 10⁻⁶ Torr. From a gas feeding source 106,GeH₄ gas at 150 SCCM, or a gas mixture thereof with PH₃ gas or B₂ H₆ gas(each diluted to 1000 ppm with hydrogen gas) at 40 SCCM was introducedinto the activation chamber (B) 123 through the gas inflow pipe 110.

GeH₄ gas, etc. introduced into the activation chamber (B) 123 wasactivated by means of the microwave plasma generating device 122 to beconverted to activated hydrogenated germanium species, etc., which werethen introduced through the inflow pipe 124 into the film formingchamber 101.

On the other hand, the activation chamber (A) 122 was packed with solidGe particles 114, heated by the electric furnace 113, thereby bringingGe into red hot state, whereinto GeF₄ was blown through the inflow pipe115 from the bomb not shown, thus forming active species of GeF₂ *,which were then introduced into the film forming chamber 101 via theinflow pipe 116.

While maintaining the inner pressure in the film forming chamber 101 at0.4 Torr, irradiation was effected vertically on the substrate 103 fromthe 1 KW Xe lamp to form non-doped or doped A-Ge(H,X) film (filmthickness 700 Å), respectively. The film forming speed was 22 Å/sec.

Subsequently, the non-doped or p-type A-Ge(H,X) film sample obtained wasplaced in a vacuum deposition tank, wherein a comb-type Al-gap electrode(length 250μ, width 5 mm) was formed under vacuum of 10.sup.⁻⁵ Torr, andthe dark electroconductivity δ_(d) was determined by measuring darkcurrent at an application voltage of 10 V for evaluation of the filmcharacteristics of the respective samples. The results are shown inTable 1D.

EXAMPLES 25-27

Except for using straight chain Ge₄ H₁₀, branched Ge₄ H₁₀, or H₆ Ge₆ F₆in place of GeH₄, A-Ge(H,X) films were formed in the same manner as inExample 24. The dark electroconductivities were measured to obtain theresults shown in Table 1D.

From Table 1D, it can be seen that A-Ge(H,X) films excellent inelectrical characteristics can be obtained and, also a-Ge(H,X) filmssubjected to satisfactory doping can be obtained according to thepresent invention.

EXAMPLE 28

By means of the device as shown in FIG. 4, a drum-shaped image formingmember for electrophotography with a layer constitution as shown in FIG.1 was prepared according to the operations as described below.

In FIG. 4, 201 shows a film forming chamber, 202 an activation chamber(A), 203 an electric furnace, 204 solid Ge particles, 205 an inflow pipefor the starting material of active species (A), 206 a pipe forintroducing active species, 207 a motor, 208 a heater which is usedsimilarly as 104 in FIG. 3, 209 and 210 are blowing pipes, 211 analuminum cylinder substrate and 212 a gas discharging valve. 213 through216 are starting gas feeding sources similarly as 106 through 109 inFIG. 3, and 217-1 is a gas introducing pipe.

In the film forming chamber 201, the aluminum cylinder 211 is suspended,equipped internally thereof with the heater 208 so as to be rotatablewith the motor 207. 218 is a photoenergy generating device, and light isirradiated toward the desired portion of the aluminum cylinder 211.

Also, the activation chamber (A) 202 was packed with solid Ge particles204, heated by the electric furnace 203 to bring C into red hot state,whereinto GeF₄ was blown into to form active species of GeF₂ *, whichwere then introduced into the film forming chamber 201 via the inflowpipe 206.

On the other hand, through the inflow pipe 217-1, Si₂ H₆, GeH₄ and H₂gases were introduced into the activation chamber (B) 219. The Si₂ H₆,GeH₄ H₂ gases introduced were subjected to activation treatment such asplasma formation by means of the microwave plasma generating device 220in the activation chamber (B) 219 to become hydrogenated silicon activespecies, hydrogenated germanium species and activated hydrogen, whichwere then introduced through the inflow pipe 217-2 into the film formingchamber 201. During this operation, if desired, impurity gases such asPH₃, B₂ H₆, etc. were also activated by introduction into the activationchamber (B) 219.

While maintaining the pressure in the film forming chamber 201 at 1.0Torr, light was irradiated from the 1 KW Xe lamp vertically onto thecircumferential surface of the aluminum cylinder 211.

The aluminum cylinder 211 was rotated, while the discharging gas wasdischarged through the discharging valve 212. Thus, a photosensitivelayer 13 was formed.

Also, the intermediate layer 12 was formed to a film thickness of 2000 Åby introducing a gas mixture of Si₂ H₆, GeH₄, H₂ and B₂ H₆ (0.2% of B₂H₆ in terms of vol. %) through the inflow pipe 217-1 prior to formationof the photosensitive layer 13.

COMPARATIVE EXAMPLE 4

According to the plasma CVD method in general, an image forming memberfor electrophotography having a layer constitution as shown in FIG. 1was formed by use of respective gases of GeF₄ and Si₂ H₆, GeH₄, H₂ andB₂ H₆ by means of the device having the same film forming chamber as thefilm forming chamber 201 provided with a high frequency means of 13.56Hz.

The conditions for preparation of the drumshaped image forming membersfor electrophotography obtained in Example 28 and Comparative example 4and their performances are shown in Table 2D.

EXAMPLE 29

By means of the device as shown in FIG. 3, with the use of GeH₄ as thegermanium-containing compound, a PIN type diode as shown in FIG. 2 wasprepared.

First, a polyethyleneterephthalate film 21 having ITO film 22 with athickness of 1000 Å vapor deposited thereon was placed on a supportingstand and, after reduced to a pressure of 10⁻⁶ Torr, active speciesGeF₂ * were introduced into the film forming chamber 101 similarly as inExample 24. Also, Si₃ H₆ gas at 150 SCCM, GeH₄ gas at 50 SCCM and PH₃gas (diluted to 1000 ppm with hydrogen gas) were respectively introducedinto the activation chamber (B) 123 to be activated. Then, the activatedgases were introduced through the inflow pipe 116 into the film formingchamber 101. While maintaining the pressure in the film forming chamberat 0.1 Torr, photoirradiation was effected by a 1 KW Xe lamp to form an-type A-SiGe(H,X) film 24 (film thickness 700 Å) doped with P.

Next, according to the same method as in formation of the n-typeA-SiGe(H,X) film except for introduction of B₂ H₆ gas (diluted to 300ppm with hydrogen gas) in place of PH₃ gas, an i-type A-SiGe(H,X) film25 (film thickness: 5000 Å) was formed.

Subsequently, by using B₂ H₆ gas (diluted to 1000 ppm with hydrogen gas)in place of PH₃ gas, following otherwise the same conditions as in thecase os n-type, an A-SiGe(H,X) film 26 (film thickness: 700 Å) dopedwith B was formed. Further, on this p-type film was formed by vapordeposition an aluminum electrode 27 with a thickness of 1000 Å toprovide a PIN type diode.

The diode element thus obtained (area 1 cm²) was subjected tomeasurement of I-V characteristic, and rectifying characteristic andphotoelectromotive effect were evaluated. The results are shown in Table3D.

Also, in photoirradiation characteristics, light was introduced from thesubstrate side, and a conversion efficiency of 7% or higher, an opencircuit voltage of 0.89 V and a short circuit current of 11.2 mA/cm²were obtained at a photoirradiation intensity AMI (about 100 mW/cm²).

EXAMPLES 30-32

Except for using straight chain Ge₄ H₁₀, branched Ge₄ H₁₀ in place ofGeH₄ as the germanium-containing compound, the same PIN type diode as inExample 29 was prepared in the same manner as in Example 29. Therectifying characteristic and photoelectromotive effect were evaluatedand the results are shown in Table 3D.

From Table 3D, it can be seen that an A-SiGe(H,X) PIN type diode havingbetter optical and electrical characteristics as compared with the priorart can be obtained according to the present invention.

EXAMPLE 34

By means of the device as shown in FIG. 3, i-type, p-type and n-typeoxygen-containing amorphous deposited films were formed according to theoperations as described below.

In FIG. 3, 101 is a film forming chamber, and a desired substrate 103 isplaced on a substrate supporting stand 102 provided internally therein.

104 is a heater for heating the substrate, which heater 104 is used forheating treatment of the substrate 103 before the film forming treatmentor, after film formation, for annealing treatment for furtherimprovement of the characteristics of the film formed, and electricityis supplied through a conductive wire 105 to generate heat. During filmformation, said heater 104 is not driven.

106 through 109 are gas feeding systems, and they are providedcorresponding to oxygen-containing compounds, and the kinds of gasesoptionally employed such as hydrogen, halogen compounds, inert gases,silicon-containing compounds, carbon-containing compounds,germanium-containing compounds, and compounds containing impurityelements as the component. When these gases employed are liquid underthe standard condition, a suitable gasifying device is provided. In thedrawing, symbols of the gas feeding sources 106 through 109 affixed witha are branched pipes, those affixed with b flowmeters, those affixedwith c pressure gauges for measuring the pressures on the higherpressure side of the respective flowmeters, those affixed with d or evalves for controlling the flow rates of respective gases.

123 is the activation chamber (B) for forming active species (B) and,around the activation chamber 124, there is provided the microwaveplasma generating device 122 for generating activation energy forformation of active species (B). The starting gas for formation ofactive species (B) supplied from the gas inflow pipe 110 is activated inthe activation chamber (B), and the active species (B) formed isintroduced through the inflow pipe 124 into the film forming chamber101.

111 is a gas pressure gauge. In the drawing, 112 shows an activationchamber (A), 113 an electric furnace, 114 solid Ge particles and 115 apipe for introduction of a gaseous compound containing germanium andhalogen as the starting material for active species (A). The activespecies (A) formed in the activation chamber 112 is introduced throughthe inflow pipe 116 into the film forming chamber 101.

117 is a photoenergy generating device and, for example, a mercury lamp,a xenon lamp, carbon dioxide laser, argon ion laser, excimer laser, etc.may be employed.

The light 118 directed to the substrate as a whole or the desiredportion of the substrate 103 by use of the suitable optical system fromthe light-energy generating device 117 is irradiated on the activespecies flowing in the direction of the arrowhead 119 to excite thegases for film forming starting materials, thereby causing them toundergo mutually chemical reaction thereby to form an oxygen-containingamorphous deposited film on the whole or the desired portion of thesubstrate 103. In the drawing, 120 shows a gas discharging valve and 121a gas discharging pipe.

First, a polyethyleneterephthalate film 103 was placed on a supportingstand 102, and the film forming chamber 101 was evacuated by use of anevacuating device to about 10⁻⁶ Torr. By use of a gas feeding source106, O₂ (diluted to 10 vol. % with He) at 150 SCCM or a gas mixturethereof with PH₃ gas or B₂ H₆ gas (each being diluted to 1000 ppm withhydrogen gas) at 40 SCCM was introduced into the activation chamber (B)123 through the gas inflow pipe 110.

O₂ gas, etc. introduced into the activation chamber (B) 123 wasactivated by means of the microwave plasma generating device 122 to beconverted to active oxygen, etc., which were then introduced through theinflow pipe 124 into the film forming chamber 101.

On the other hand, the activation chamber (A) 112 was packed with solidGe particles 114, heated by the electric furnace 113 to be maintained atabout 1100° C., thereby bringing Ge into red hot state, whereinto GeF₄was blown through the inflow pipe 115 from the bomb not shown, thusforming active species of GeF₂ *, which were then introduced into thefilm forming chamber 101 via the inflow pipe 116.

While maintaining the inner pressure in the film forming chamber 101 at0.4 Torr, irradiation was effected vertically on the substrate 103 fromthe 1 KW Xe lamp to form a non-doped or doped oxygen-containingamorphous film (film thickness 700 Å). The film forming speed was 22Å/sec.

Subsequently, the respective non-doped or p-type samples obtained wereplaced in a vacuum deposition tank, wherein comb-type Al-gap electrodes(length 250μ, width 5 mm) were formed under vacuum of 10⁻⁵ Torr, and thedark electroconductivity δ_(d) was determined by measuring dark currentat an applied voltage of 10 V for evaluation of the film characteristicsof the respective samples. The results are shown in Table 1E.

EXAMPLES 35-37

Except for introducing O₂ (diluted to 10 vol. %), Si₂ F₆, Ge₂ F₆ and C₂H₆ at a use ratio of 1:9, oxygen-containing amorphous deposited filmswere formed according to the same procedures as in Example 34. The darkelectroconductivities were measured to obtain the results shown in Table1E.

From Table 1E, it can be seen that oxygen-containing amorphous depositedfilms excellent in electrical characteristics can be obtained accordingto the present invention.

EXAMPLES 38-41

Following the same procedures as in Example 56, except for using H₃SiOSiH₃, H₃ GeOGeH₃, CO₂ or OF₂, oxygen-containing amorphous depositedfilms were formed.

The thus obtained oxyge-containing amorphous deposited films were foundto be excellent in electrical characteristics and sufficiently doped.

EXAMPLE 42

By means of the device as shown in FIG. 4, a drum-shaped image formingmember for electrophotography with a layer constitution as shown in FIG.1 was prepared according to the operations as described below.

In FIG. 4, 201 shows a film forming chamber, 202 an activation chamber(A), 203 an electric furnace, 204 solid Ge particles, 205 an inflow pipefor the starting material of active species (A), 206 a pipe forintroducing active species (A), 207 a motor, 208 a heater which is usedsimilarly as 104 in FIG. 3, 209 and 210 are blowing pipes, 211 analuminum cylinder and 212 a gas discharging valve. 213 through 216 arestarting gas feeding sources similarly as 106 through 109 in FIG. 3, and217-1 is a gas introducing pipe.

In the film forming chamber 201, the aluminum cylinder 211 is suspended,equipped internally thereof with the heater 208 so as to be rotatablewith the motor 207. 218 is a photoenergy generating device, and light isirradiated toward the desired portion of the aluminum cylinder 211.

Also, the activation chamber (A) 202 is packed with solid Ge particles204, heated by the electric furnace 203 to bring Ge into red hot state,whereinto GeF₄ is blown through the inflow pipe 206 from the bomb notshown to form active species (A) of GeF₂ *, which are then introducedinto the film forming chamber 201 via the inflow pipe 206.

On the other hand, through the inflow pipe 217-1, the respective gasesof O₂, Si₂ F₆ and H₂ were introduced into the activation chamber (B)219. The O₂, Si₂ F₆ and H₂ gases introduced were subjected to activationtreatment such as plasma formation by means of the microwave plasmagenerating device 220 in the activation chamber (B) 219 to becomeactivated oxygen, activated hydrogen, activated silicon, etc., whichwere then introduced through the inflow pipe 217-2 into the film formingchamber 201. During this operation, if desired, impurity gases such asPH₃, B₂ H₆, etc. were also activated by introduction into the activationchamber (B) 220.

While maintaining the pressure in the film forming chamber 201 at 1.0Torr, light was irradiated from the 1 KW Xe lamp vertically onto thecircumferential surface of the aluminum cylinder 211.

The aluminum cylinder 211 was rotated, while the discharging gas wasdischarged by controlling adequately the opening of the dischargingvalve 212. Thus, a photosensitive layer 13 was formed.

Also, the intermediate layer 12 was formed before formation of thephotosensitive layer to a film thickness of 2000 Å by introducing Si₂F₆, O₂ (Si₂ F₆ :O₂ =1:10⁻⁵), He and B₂ H₆ (0.2% of B₂ H₆ in terms ofvol. %) through the inflow pipe 217-1.

COMPARATIVE EXAMPLE 5

According to the plasma CVD method in general, a drum-shaped imageforming member for electrophotography having a layer constitution asshown in FIG. 1 was formed by use of respective gases of GeF₄, Si₂ F₆,O₂, He and B₂ H₆ by means of the device having the same film formingchamber as the film forming chamber 201 provided with a high frequencymeans of 13.56 MHz.

The conditions for preparation of the drum-shaped image forming membersfor electrophotography obtained in Example 42 and Comparative example 5and their performances are shown in Table 2E.

EXAMPLE 43

By means of the device as shown in FIG. 3, a PIN type diode as shown inFIG. 2 was prepared.

First, a polyethyleneterephthalate film 21 having ITO film 22 with athickness of 1000 Å vapor deposited thereon was placed on a supportingstand and, after reduced to a pressure of 10⁻⁶ Torr, active speciesGeF₂ * were introduced into the film forming chamber 101 similarly as inExample 24. Also, Si₂ F₆ gas and PH₃ gase (diluted to 1000 ppm withhydrogen gas) were respectively introduced into the activation chamber(B) 123 to be activated.

Then, the activated gases were introduced through the inflow pipe 116into the film forming chamber 101. While maintaining the pressure in thefilm forming chamber at 0.3 Torr, photoirradiation was effected by a 1KW Xe lamp to form a n-type A-SiGe(H,X) film 24 (film thickness 700 A)doped with P.

Next, according to the same method as in formation of the n-typeA-SiGe(H,X) film except for stopping introduction of PH₃ gas, anon-doped a-SiGe(H,X) film 25 (film thickness: 5000 Å) was formed.

Subsequently, by using O₂ gas and B₂ H₆ gas (diluted to 1000 ppm withhydrogen gas) together with Si₂ F₆ gas, following otherwise the sameconditions as in the case of n-type, a p-type oxygen-containinga-SiGeO(H,X) film 26 (film thickness: 700 Å) doped with B was formed.Further, on this p-type film was formed by vapor deposition an aluminumelectrode 27 with a thickness of 1000 Å to provide a PIN type diode.

The diode element thus obtained (area 1 cm²) was subjected tomeasurement of I-V characteristic, and rectifying characteristic andphotoelectromotive effect were evaluated. The results are shown in Table3E.

Also, in photoirradiation characteristics, light was introduced from thesubstrate side, and a conversion efficiency of 8.2% or higher, an opencircuit voltage of 0.93 V and a short circuit current of 9.8 mA/cm² wereobtained at a photoirradiation intensity AMI (about 100 mW/cm²).

EXAMPLES 44-46

Except for using H₃ SiOSiH₃, H₃ GeOGeH₃ or OF₂ in place of O₂ as theoxygen compound, the same PIN type diode as in Example 43 was preparedin the same manner as in Example 43. The rectifying characteristic andphotoelectromotive effect were evaluated and the results are shown inTable 3E.

From Table 3E, it can be seen that an oxygen-containing A-SiGe(H,X) PINtype diode having better optical and electrical characteristics ascompared with the prior art can be obtained according to the presentinvention.

EXAMPLE 47

By means of the device as shown in FIG. 3, i-type, p-type and n-typenitrogen-containing amorphous deposited films were formed according tothe operations as described below.

In FIG. 3, 101 is a film forming chamber, and a desired substrate 103 isplaced on a substrate supporting stand 102 provided internally therein.

104 is a heater for heating the substrate, which heater 104 is used forheating treatment of the substrate 103 before the film forming treatmentor, after film formation, for annealing treatment for furtherimprovement of the characteristics of the film formed, and electricallyis supplied through a conductive wire 105 to generate heat. During filmformation, said heater 104 is not driven.

106 through 109 are gas feeding sources, and they are providedcorresponding to the nitrogen-containing compounds, and the kinds ofgases optionally employed such as hydrogen, halogen compounds, inertgases, silicon-containing compounds, carbon-containing compounds,germanium-containing compounds oxygen containing compound and compoundscontaining impurity elements as the component. When these gases employedare liquid under the standard condition, a suitable gasifying device isprovided.

In the drawing, symbols of the gas feeding sources 106 through 109affixed with a are branched pipes, those affixed with b flowmeters,those affixed with c pressure gauges for measuring the pressures on thehigher pressure side of the respective flowmeters, those affixed with dor e valves for controlling the flow rates of respective gases.

123 is the activation chamber (B) for forming active species (B) and,around the activation chamber 123, there is provided the microwaveplasma generating device 122 for generating activation energy forformation of active species (B). The starting gas for formation ofactive species (B) supplied from the gas inflow pipe 110 is activated inthe activation chamber (B), and the active species (B) formed isintroduced through the inflow pipe 124 into the film forming chamber101. 110 is a gas inflow pipe into the film forming chamber, and 111 isa gas pressure gauge. In the drawing, 112 shows an activation chamber(A), 113 an electric furnace, 114 solid Ge particles and 115 a pipe forintroduction of a gaseous compound containing germanium and halogen asthe starting material for active species (A). The active species (A)formed in the activation chamber 112 is introduced through the inflowpipe 116 into the film forming chamber 101.

117 is a photoenergy generating device and, for example, a mercury lamp,a xenon lamp, carbon dioxide laser, argon ion laser, excimer laser, etc.may be employed.

The light directed to the substrate as a whole or the desired portion ofthe substrate 103 by use of a suitable optical system from thelight-energy generating device 117 is irradiated on the active speciesflowing in the direction of the arrowhead 119, and the irradiated activespecies undergo mutually chemical reaction thereby to form anitrogen-containing amorphous deposited film on the whole or the desiredportion of the substrate 103.

In the drawing, 120 shows a gas discharging valve and 121 a gasdischarging pipe.

First, a polyethyleneterephthalate film 103 was placed on a supportingstand 102, and the film forming chamber 101 was evacuated by use of anevacuating device (not shown) to about 10⁻⁶ Torr. From a gas feedingsource 106, N₂ at 150 SCCM or a gas mixture thereof with PH₃ gas or B₂H₆ gas (each being diluted to 1000 ppm with hydrogen gas) at 40 SCCM wasintroduced into the activation chamber (B) 123 through the gas inflowpipe 110. N₂ gas, etc. introduced into the activation chamber (B) 123was activated by means of the microwave plasma generating device 122 tobe converted to activated nitrogen, etc., which were then introducedthrough the inflow pipe 124 into the film forming chamber 101.

On the other hand, the activation chamber (A) 122 was packed with solidGe particles 114, heated by the electric furnace 113 to be maintained atabout 1100° C., thereby bringing Ge into red hot state, whereinto GeF₄was blown through the inflow pipe 115 from the bomb not shown, thusforming active species of GeF₂ *, which were then introduced into thefilm forming chamber 101 via the inflow pipe 116.

While maintaining the inner pressure in the film forming chamber 101 at0.1 Torr, irradiation was effected vertically on the substrate 103 fromthe 1 KW Xe lamp to form a nitrogen-containing amorphous deposited film(film thickness 700 Å). The film forming speed was 30 Å/sec.

Subsequently, each of non-doped, p-type and n-type samples obtained wasplaced in a vacuum deposition tank, wherein a comb-type Al-gap electrode(length 250μ, width 5 mm) was formed under vacuum of 10⁻⁵ Torr, and thedark electroconductivity δ_(d) was determined by measuring dark currentat an applied voltage of 12 V for evaluation of the film characteristicsof the respective samples. The results are shown in Table 1F.

EXAMPLES 48-50

Except for using Si₂ H₆, Ge₂ H₆ or C₂ H₆ together with H₂nitrogen-containing amorphous deposited films were formed according tothe same procedures as in Example 47. The dark electroconductivitieswere measured for respective samples to obtain the results shown inTable 1F.

From Table 1F, it can be seen that nitrogen-containing amorphous filmsexcellent in electrical characteristics can be obtained according to thepresent invention, and also that nitrogen-containing amorphous depositedfilms sufficiently doped can be obtained.

EXAMPLES 51-54

In the same manner as in Example 47, except for using NH₃, NOF, NO₂ orN₂ O in place of N₂, nitrogen-containing amorphous deposited films wereformed.

The nitrogen-containing amorphous deposited films were found to beexcellent in electrical characteristics and also sufficiently doped.

EXAMPLE 55

By means of the device as shown in FIG. 4, a drum-shaped image formingmember for electrophotography with a layer constitution as shown in FIG.1 was prepared according to the operations as described below.

In FIG. 4, 201 shows a film forming chamber, 202 an activation chamber(A), 203 an electric furnace, 204 solid Si particles, 205 an inflow pipefor the starting material of active species (A), 206 a pipe forintroducing active species, 207 a motor, 208 a heater which is usedsimilarly as 104 in FIG. 2, 209 and 210 are blowing pipes, 211 analuminum cylinder substrate and 212 a gas discharging valve. 213 through216 are starting gas feeding sources similarly as 106 through 109 inFIG. 3, and 217-1 is a gas introducing pipe.

In the film forming chamber 201, the aluminum cylinder 211 wassuspended, equipped internally thereof with the heater 208 so as to berotatable with the motor 207. 218 is a photoenergy generating device,and light was irradiated toward the desired portion of the aluminumcylinder 211.

Also, the activation chamber (A) 202 was packed with solid Ge particles204, heated by the electric furnace 203 to be maintained at about 1100°C. to bring Ge into red hot state, whereinto GeF₄ was blown into to formactive species of GeF₂ *, which were then introduced into the filmforming chamber 201 via the inflow pipe 206.

On the other hand, through the inflow pipe 217-1, respective gases ofSi₂ H₆ and N₂ were introduced into the activation chamber (B) 219. TheSi₂ H₆ and N₂ gases introduced were subjected to activation treatmentsuch as plasma formation by means of the microwave plasma generatingdevice 220 in the activation chamber (B) 219 to become activatedhydrogenated silicon and activated hydrogen, which were then introducedthrough the inflow pipe 217-2 into the film forming chamber 201. Duringthis operation, if desired, impurity gases such as PH₃, B₂ H₆, etc. werealso introduced into the activation chamber (B) 220 to be activated.While maintaining the pressure in the film forming chamber 201 at 1.0Torr, light was irradiated from the 1 KW Xe lamp 218 vertically onto thecircumferential surface of the aluminum cylinder 211.

The aluminum cylinder 211 was rotated, while the discharging gas wasdischarged through the discharging valve 212. Thus, photosensitive layer13 was formed.

Also, the intermediate layer 12 was formed before formation of thephotosensitive layer 13 to a film thickness of 2000 Å by introducing agas mixture of Si₂ H₆, N₂, H₂ and B₂ H₆ (0.2% of B₂ H₆ in terms of vol.%) in addition to the gases employed in preparation of thephotosensitive layer 13 through the inflow pipe 217-1.

COMPARATIVE EXAMPLE 6

According to the plasma CVD method in general, an image forming memberfor electrophotography having a layer constitution as shown in FIG. 1Cwas formed by use of respective gases of GeF₄, Si₂ H₆, N₂, and H₂ and B₂H₆ by means of the device having the same film forming chamber as thefilm forming chamber 201 provided with a high frequency generator of13.56 MHz.

The conditions for preparation of the drum-shaped image forming membersfor electrophotography obtained in Example 55 and Comparative example 6and their performances are shown in Table 2F.

EXAMPLE 56

By use of N₂ as the nitrogen compound, by means of the device as shownin FIG. 3, a PIN type diode as shown in FIG. 2 was prepared.

First, a polyethyleneterephthalate film 21 having ITO film 22 with athickness of 1000 Å vapor deposited thereon was placed on a supportingstand and, after reduced to a pressure of 10⁻⁶ Torr, active speciesGeF₂ * formed similarly as in Example 47 were introduced into the filmforming chamber 101. Also, Si₃ H₆ gas and PH₃ gas (diluted to 1000 ppmwith hydrogen gas) were respectively introduced into the activationchamber (B) 123 to be activated. Then, the activated gases wereintroduced through the inflow pipe 116 into the film forming chamber101. While maintaining the pressure in the film forming chamber at 0.4Torr, photoirradiation was effected by a 4 KW Xe lamp to form a n-typeA-SiGeN(H,X) film 24 (film thickness 700 Å) doped with P.

Next, according to the same method as in formation of the n-typeA-Si(H,X) film except for stopping introduction of PH₃ gas, a non-dopedA-SiGeN(H,X) film 25 (film thickness: 5000 Å) was formed.

Subsequently, by using N₂ gas and B₂ H₆ gas (diluted to 1000 ppm withhydrogen gas) together with Si₂ H₆ gas, following otherwise the sameconditions as in the case of n-type, a p-type A-SiGeN(H,X) film 26 (filmthickness: 700 Å) doped with B was formed. Further, on this p-type filmwas formed by vapor deposition an aluminum electrode 27 with a thicknessof 1000 Å to provide a PIN type diode.

The diode element thus obtained (area 1 cm²) was subjected tomeasurement of I-V characteristic, and rectifying characteristic andphotoelectromotive effect were evaluated. The results are shown in Table3F.

Also, in photoirradiation characteristics, light was introduced from thesubstrate side, and a conversion efficiency of 8.4% or higher, an opencircuit voltage of 0.9 V and a short circuit current of 10.2 mA/cm² wereobtained at a photoirradiation intensity AMI (about 100 mW/cm²).

EXAMPLES 57-59

Except for using NO, N₂ O, N₂ O₄ in place of N₂ as the nitrogencompound, the same PIN type diode as in Example 56 was prepared in thesame manner as in Example 56. The rectifying characteristic andphotoelectromotive effect were evaluated and the results are shown inTable 3F.

                  TABLE 1A                                                        ______________________________________                                                       Example 1                                                                             Example 2                                              ______________________________________                                        Starting gas for H.sub.2   H.sub.2 /F.sub.2                                   formation of active                                                           species (B)                                                                   σ.sub.d (Non-doped)                                                                      8.8 × 10.sup.-4                                                                   7.6 × 10.sup.-4                              (Ω · cm).sup.-1                                                σ.sub.d (B doped)                                                                        7.1 × 10.sup.-3                                                                   3.3 × 10.sup.-3                              (Ω · cm).sup.-1                                                σ.sub.d (P doped)                                                                        6.7 × 10.sup.-3                                                                   7.2 × 10.sup.-3                              (Ω · cm).sup.-1                                                ______________________________________                                    

                                      TABLE 2A                                    __________________________________________________________________________                 Example 3    Comparative example 1                               __________________________________________________________________________    Starting gas for formation                                                                 GeF.sub.4 /SiF.sub.4                                             of active species (A)                                                         Activation temperature                                                                     1000° C.                                                  Main decomposed active                                                                     GeF.sub.2 *                                                      species      SiF.sub.2 *                                                      Starting gas for formation                                                                 H.sub.2                                                          of active species (B)                                                         Inflow amount from                                                                         200 SCCM                                                         activation chamber (A)                                                        Inflow amount from                                                                         100 SCCM                                                         activation chamber (B)                                                        Inflow amount from        GeF.sub.4 100 SCCM                                  starting gas bomb         SiF.sub.4 200 SCCM                                                            H.sub.2 100 SCCM                                    Inner pressure in film                                                                     0.8 Torr     1.0 Torr                                            forming chamber                                                               Film forming rate                                                                          17.5 Å/sec                                                                             5 Å/sec                                         RF discharging power      1.8 W/cm.sup.2                                      Layer thickness of                                                                         22μ       22μ                                              photosensitive layer 13                                                       Average number of image                                                                    3            21                                                  defects in 10 drum-shaped                                                     image forming members                                                         for electrophotography                                                        Acceptance potential                                                                       ±12 V     ±35 V                                            irregularity in                                                               circumferential direction                                                     Acceptance potential                                                                       ±17 V     ±40 V                                            irregularity in axial                                                         direction                                                                     Remarks      Example according to the                                                                   Example according to plasma                                      process of this invention                                                                  CVD of the prior art                                                          Substrate temperature 250° C.                __________________________________________________________________________

                  TABLE 3A                                                        ______________________________________                                                          Example 4                                                                             Example 5                                           ______________________________________                                        Gas for film formation starting gas                                                               H.sub.2   H.sub.2 /F.sub.2                                Rectifying ratio of diode (*1)                                                                    5.5 × 10.sup.2                                                                    4.8 × 10.sup.2                            η value of diode (*2)                                                                         1.3       1.4                                             ______________________________________                                         (*1) Ratio of forward current to reverse current at voltage 1 V               (*2) η value (Quality Factor) in the current formula of p - n             junction:                                                                     ##STR1##                                                                 

                                      TABLE 1B                                    __________________________________________________________________________                 Example 6                                                                           Example 7                                                                           Example 8                                                                           Example 9                                      __________________________________________________________________________    Starting gas for formation                                                                 Si.sub.5 H.sub.10                                                                   Si.sub.4 H.sub.10                                                                   SiH.sub.3 SiH                                                                       H.sub.6 Si.sub.6 F.sub.6                       of active species (B)    (SiH.sub.3)Si                                                                 H.sub.3                                              δ.sub.d (Non-doped)                                                                  6.6 × 10.sup.-9                                                               7.3 × 10.sup.-9                                                               5.5 × 10.sup.-9                                                               4.7 × 10.sup.-9                          (Ω · cm).sup.-1                                                δ.sub.d (B doped)                                                                    7.3 × 10.sup.-6                                                               5.3 × 10.sup.-6                                                               5.6 × 10.sup.-6                                                               3.8 × 10.sup.-6                          (Ω · cm).sup.-1                                                δ.sub.d (P doped)                                                                    5.5 × 10.sup.-6                                                               8.2 × 10.sup.-6                                                               6.1 × 10.sup.-6                                                               4.0 × 10.sup.-6                          (Ω · cm).sup.-1                                                __________________________________________________________________________

                                      TABLE 2B                                    __________________________________________________________________________                  Example 10   Comparative example 2                              __________________________________________________________________________    Starting gas for formation                                                                  GeF.sub.4                                                       of active species (A)                                                         Decomposition temperature                                                                   1100° C.                                                 Main decomposed                                                                             GeF.sub.2 *                                                     active species                                                                Starting gas for formation                                                                  Si.sub.2 H.sub.6 /H.sub.2                                       Inflow amount from                                                                          200 SCCM                                                        activation chamber (A)                                                        Inflow amount from                                                                          100 SCCM                                                        activation chamber (B)                                                        Inflow amount from        GeF.sub.4 200 SCCM                                  starting gas bomb         Si.sub.2 H.sub.6 100 SCCM                                                     H.sub.2 100 SCCM                                    Inner pressure in film                                                                      1.0 Torr    1.0 Torr                                            forming chamber                                                               Film forming rate                                                                           19 Å/sec                                                                              6 Å/sec                                         RF discharging power      1.8 W/cm.sup.2                                      Layer thickness of                                                                          22μ      22μ                                              photosensitive layer 13                                                       Average number of image                                                                     3           16                                                  defects in 10 drum-shaped                                                     image forming members                                                         for electrophotography                                                        Acceptance potential                                                                        ±9 V     ±31 V                                            irregularity in                                                               circumferential direction                                                     Acceptance potential                                                                        ±15 V    ±35 V                                            irregularity in axial                                                         direction                                                                     Remarks       Example according to the                                                                  Example according to plasma                                       process of this invention                                                                 CVD of the prior art                                                          Substrate temperature 250° C.                __________________________________________________________________________

                  TABLE 3B                                                        ______________________________________                                                Example                                                                              Example                                                                11     12       Example 13                                                                              Example 14                                  ______________________________________                                        Gas for film                                                                            Si.sub.3 H.sub.6                                                                       Si.sub.4 H.sub.10                                                                      SiH.sub.3 SiH--                                                                       H.sub.6 Ge.sub.6 F.sub.6                  formation                   (SiH.sub.3)--                                     starting gas                SiH.sub.3                                         Rectifying ratio                                                                        7 × 10.sup.2                                                                     6 × 10.sup.2                                                                     8.3 × 10.sup.2                                                                  7.7 × 10.sup.2                      of diode (*1)                                                                 η value of                                                                          1.1      1.4      1.5     1.3                                       diode (*2)                                                                    ______________________________________                                         (*1) Ratio of forward current to reverse current at voltage 1 V               (*2) η value (Quality Factor) in the current formula of p - n             junction:                                                                     ##STR2##                                                                 

                                      TABLE 1C                                    __________________________________________________________________________                 Example 15                                                                          Example 16                                                                          Example 17                                                                          Example 18                                     __________________________________________________________________________    Starting gas for formation                                                                 CH.sub.4                                                                            C.sub.2 H.sub.6                                                                     C.sub.2 H.sub.4                                                                     C.sub.2 H.sub.2                                of active species (B)                                                         δ.sub.d (Non-doped)                                                                  6.8 × 10.sup.-9                                                               4.4 × 10.sup.-9                                                               4.8 × 10.sup.-9                                                               3.2 × 10.sup.-9                          (Ω · cm).sup.-1                                                δ.sub.d (B doped)                                                                    6.8 × 10.sup.-6                                                               3.5 × 10.sup.-6                                                               4.3 × 10.sup.-6                                                               4.1 × 10.sup.-6                          (Ω · cm).sup.-1                                                δ.sub.d (P doped)                                                                    5.0 × 10.sup.-6                                                               4.8 × 10.sup.-6                                                               5.2 × 10.sup.-6                                                               5.9 × 10.sup.-6                          (Ω · cm).sup.-1                                                __________________________________________________________________________

                                      TABLE 2C                                    __________________________________________________________________________                 Example 19   Comparative example 3                               __________________________________________________________________________    Starting gas for formation                                                                 GeF.sub.4                                                        of active species (A)                                                         Activation temperature                                                                     1100° C.                                                  Main         GeF.sub.2 *                                                      active species                                                                Starting gas for formation                                                                 CH.sub.4 /Si.sub.2                                               of active species (B)                                                                      H.sub.6 /H.sub.2                                                              Volume ratio                                                                  0.1:2:0.1                                                        Inflow amount from                                                                         210 SCCM                                                         activation chamber (A)                                                        Inflow amount from                                                                         120 SCCM                                                         activation chamber (B)                                                        Inflow amount from        GeF.sub.4 200 SCCM                                  starting gas bomb         CH.sub.4 50 SCCM                                                              Si.sub.2 H.sub.6 100 SCCM                                                     H.sub.2 100 SCCM                                    Inner pressure in film                                                                     1.0 Torr     1.0 Torr                                            forming chamber                                                               Film forming rate                                                                          16 Å/sec 5 Å/sec                                         RF discharging power      1.5 W/cm.sup.2                                      Layer thickness of                                                                         23μ       23μ                                              photosensitive layer 13                                                       Average number of image                                                                    3            16                                                  defects in 10 drum-shaped                                                     image forming members                                                         for electrophotography                                                        Acceptance potential                                                                       ±8 V      ±30 V                                            irregularity in                                                               circumferential direction                                                     Acceptance potential                                                                       ±16 V     ±35 V                                            irregularity in axial                                                         direction                                                                     Remarks      Example according to the                                                                   Example according to plasma                                      process of this invention                                                                  CVD of the prior art                                                          Substrate temperature 250° C.                __________________________________________________________________________

                                      TABLE 3C                                    __________________________________________________________________________                 Example 20                                                                          Example 21                                                                          Example 22                                                                          Example 23                                     __________________________________________________________________________    Starting gas for formation                                                                 CH.sub.4                                                                            C.sub.2 H.sub.6                                                                     C.sub.2 H.sub.4                                                                     C.sub.2 H.sub.2                                of active species (B)                                                         Rectifying ratio of                                                                        5 × 10.sup.2                                                                  7 × 10.sup.2                                                                  6.5 × 10.sup.2                                                                5.5 × 10.sup.2                           diode (1*)                                                                    η value of diode (*2)                                                                  1.3   1.35  1.4   1.25                                           __________________________________________________________________________     (*1) Ratio of forward current to reverse current at voltage 1 V               (*2) η value (Quality Factor) in the current formula of p - n             junction:                                                                     ##STR3##                                                                 

                                      TABLE 1D                                    __________________________________________________________________________                 Example 24                                                                          Example 25                                                                           Example 26                                                                          Example 27                                    __________________________________________________________________________    Starting gas for formation                                                                 GeH.sub.4                                                                           Straight chain                                                                       Branched                                                                            H.sub.6 Ge.sub.6 F.sub.6                      of active species (B)                                                                            Ge.sub.4 H.sub.10                                                                    Ge.sub.4 H.sub.10                                   δ.sub.d (Non-doped)                                                                  9.1 × 10.sup.-4                                                               7.7 × 10.sup.-4                                                                8.1 × 10.sup.-4                                                               6.5 × 10.sup.-4                         (Ω · cm).sup.-1                                                δ.sub.d (B doped)                                                                      8 × 10.sup.-3                                                               4 × 10.sup.-3                                                                  3.6 × 10.sup.-3                                                               7.0 × 10.sup.-3                         (Ω · cm).sup.-1                                                δ.sub.d (P doped)                                                                      9 × 10.sup.-3                                                               5 × 10.sup.-3                                                                    4 × 10.sup.-3                                                               7.5 × 10.sup.-3                         (Ω · cm).sup.-1                                                __________________________________________________________________________

                                      TABLE 2D                                    __________________________________________________________________________                 Example 28   Comparative example 4                               __________________________________________________________________________    Starting gas for formation                                                                 GeF.sub.4                                                        of active species (A)                                                         Activation temperature                                                                     1100° C.                                                  Main decomposed active                                                                     GeF.sub.2 *                                                      species                                                                       Starting gas for formation                                                                 Si.sub.2 H.sub.6 /                                               of active species (B)                                                                      GeH.sub.4 /H.sub.2                                               Inflow amount from                                                                         250 SCCM                                                         activation chamber (A)                                                        Inflow amount from                                                                         150 SCCM                                                         activation chamber (B)                                                        Inflow amount from        GeF.sub.4 200 SCCM                                  starting gas bomb         Si.sub.2 H.sub.6 100 SCCM                                                     GeH.sub.4 50 SCCM                                                             H.sub.2 100 SCCM                                    Inner pressure in film                                                                     1.0 Torr     1.0 Torr                                            forming chamber                                                               Film forming rate                                                                          20 Å/sec 5 Å/sec                                         RF discharging power      0.19 W/cm.sup.2                                     Layer thickness of                                                                         23μ       23μ                                              photosensitive layer 13                                                       Average number of image                                                                    5            26                                                  defects in 10 drum-shaped                                                     image forming members                                                         for electrophotography                                                        Acceptance potential                                                                       ±13 V     ±35 V                                            irregularity in                                                               circumferential direction                                                     Acceptance potential                                                                       ±17 V     ±40 V                                            irregularity in axial                                                         direction                                                                     Remarks      Example according to the                                                                   Example according to plasma                                      process of this invention                                                                  CVD of the prior art                                                          Substrate temperature 250° C.                __________________________________________________________________________

                                      TABLE 3D                                    __________________________________________________________________________                 Example 29                                                                          Example 30                                                                           Example 31                                                                          Example 32                                    __________________________________________________________________________    Starting gas for formation                                                                 GeH.sub.4                                                                           Straight chain                                                                       Branched                                                                            H.sub.6 Ge.sub.6 F.sub.6                      of active species (B)                                                                            Ge.sub.4 H.sub.10                                                                    Ge.sub.4 H.sub.10                                   Rectifying ratio of                                                                        7.6 × 10.sup.2                                                                7.7 × 10.sup.2                                                                 7.3 × 10.sup.2                                                                8.0 × 10.sup.2                          diode (*1)                                                                    η value of diode (*2)                                                                  1.31  1.21   1.28  1.36                                          __________________________________________________________________________     (*1) Ratio of forward current to reverse current at voltage 1 V               (*2) η value (Quality Factor) in the current formula of p - n             junction:                                                                     ##STR4##                                                                 

                                      TABLE 1E                                    __________________________________________________________________________                 Example 34                                                                          Example 35                                                                          Example 36                                                                          Example 37                                     __________________________________________________________________________    Starting gas for formation                                                                 O.sub.2 /He                                                                         O.sub.2 /He/                                                                        O.sub.2 /He/                                                                        O.sub.2 /He/                                   of active species (B)                                                                            Si.sub.2 H.sub.6                                                                    Ge.sub.2 H.sub.6                                                                    C.sub.2 H.sub.6                                δ.sub.d (Non-doped)                                                                  3.5 × 10.sup.-9                                                               1.5 × 10.sup.-9                                                               4.3 × 10.sup.-9                                                               .sup. 7.1 × 10.sup.-10                   (Ω · cm).sup.-1                                                δ.sub.d (B doped)                                                                    8.4 × 10.sup.-6                                                               9.5 × 10.sup.-6                                                               8.9 × 10.sup.-6                                                               3.3 × 10.sup.-7                          (Ω · cm).sup.-1                                                δ.sub.d (P doped)                                                                    9.0 × 10.sup.-6                                                               1.0 × 10.sup.-5                                                               9.5 × 10.sup.-6                                                               3.5 × 10.sup.-7                          (Ω · cm).sup.-1                                                __________________________________________________________________________

                                      TABLE 2E                                    __________________________________________________________________________                 Example 42   Comparative example 5                               __________________________________________________________________________    Starting gas for formation                                                                 GeF.sub.4                                                        of active species (A)                                                         Activation temperature                                                                     1100° C.                                                  Main active species                                                                        GeF.sub.2 *                                                      Starting gas for formation                                                                 Si.sub.2 F.sub.6 /                                               of active species (B)                                                                      O.sub.2 /H.sub.e                                                 Inflow amount from                                                                         250 SCCM                                                         activation chamber (A)                                                        Inflow amount from                                                                         150 SCCM                                                         activation chamber (B)                                                        Inflow amount from        GeF.sub.4 200 SCCM                                  starting gas bomb         Si.sub.2 F.sub.6 100 SCCM                                                     O.sub.2 (Si.sub.2 H.sub.6 :                                                   O.sub.2 = 1:10.sup.5)                                                         He 100 SCCM                                         Inner pressure in film                                                                     1.0 Torr     1.0 Torr                                            forming chamber                                                               Film forming rate                                                                          20 Å/sec 5 Å/sec                                         RF discharging power      1.6 W/cm.sup.2                                      Layer thickness of                                                                         25μ       25μ                                              photosensitive layer 13                                                       Average number of image                                                                    3            20                                                  defects in 10 drum-shaped                                                     image forming members                                                         for electrophotography                                                        Acceptance potential                                                                       ±9 V      ±30 V                                            irregularity in                                                               circumferential direction                                                     Acceptance potential                                                                       ±14 V     ±35 V                                            irregularity in axial                                                         direction                                                                     Remarks      Example according to the                                                                   Example according to plasma                                      process of this invention                                                                  CVD of the prior art                                                          Substrate temperature 250° C.                __________________________________________________________________________

                                      TABLE 3E                                    __________________________________________________________________________                 Example 43                                                                          Example 44                                                                          Example 45                                                                           Example 46                                    __________________________________________________________________________    Starting gas for formation                                                                 O.sub.2                                                                             H.sub.3 SiOSiH.sub.3                                                                H.sub.3 GeOGeH.sub.3                                                                 OF.sub.2                                      of active species (B)                                                         Rectifying ratio of                                                                        4 × 10.sup.2                                                                  7 × 10.sup.2                                                                  6 × 10.sup.2                                                                   5 × 10.sup.2                            diode (*1)                                                                    η value of diode (*2)                                                                  1.4   1.3   1.2    1.3                                           __________________________________________________________________________     (*1) Ratio of forward current to reverse current at voltage 1 V               (*2) η value (Quality Factor) in the current formula of p - n             junction:                                                                     ##STR5##                                                                 

                                      TABLE 1F                                    __________________________________________________________________________                 Example 47                                                                          Example 48                                                                          Example 49                                                                           Example 50                                    __________________________________________________________________________    Starting gas for formation                                                                 N.sub.2                                                                             N.sub.2 /Si.sub.2 H.sub.6                                                           N.sub.2 /Ge.sub.2 H.sub.6                                                            N.sub.2 /C.sub.2 H.sub.6                      of active species (B)                                                         δ.sub.d (Non-doped)                                                                  5.0 × 10.sup.-9                                                               8.0 × 10.sup.-9                                                               4.5 × 10.sup.-9                                                                .sup.  6.6 × 10.sup.-10                 (Ω · cm).sup.-1                                                δ.sub.d (B doped)                                                                      1 × 10.sup.-6                                                               5.0 × 10.sup.-6                                                               4.1 × 10.sup.-6                                                                8.8 × 10.sup.-7                         (Ω · cm).sup.-1                                                δ.sub.d (P doped)                                                                      7 × 10.sup.-6                                                               5.0 × 10.sup.-5                                                               1.1 × 10.sup.-5                                                                6 × 10.sup.-6                           (Ω · cm).sup.-1                                                __________________________________________________________________________

                                      TABLE 2F                                    __________________________________________________________________________                 Example 55   Comparative example 6                               __________________________________________________________________________    Starting gas for formation                                                                 GeF.sub.4                                                        of active species (A)                                                         Activation temperature                                                                     1100° C.                                                  Main active species                                                                        GeF.sub.2 *                                                      Starting gas for formation                                                                 Si.sub.2 H.sub.6 /                                               of active species (B)                                                                      N.sub.2 /H.sub.2                                                 Inflow amount from                                                                         210 SCCM                                                         activation chamber (A)                                                        Inflow amount from                                                                         100 SCCM                                                         activation chamber (B)                                                        Inflow amount from        GeF.sub.4 200 SCCM                                  starting gas bomb         Si.sub.2 H.sub.6 100 SCCM                                                     N.sub.2 50 SCCM                                                               H.sub.2 100 SCCM                                    Inner pressure in film                                                                     1.0 Torr     1.0 Torr                                            forming chamber                                                               Film forming rate                                                                          15 Å/sec 5 Å/sec                                         RF discharging power      1.9 W/cm.sup.2                                      Layer thickness of                                                                         22μ       22μ                                              photosensitive layer 13                                                       Average number of image                                                                    2            20                                                  defects in 10 drum-shaped                                                     image forming members                                                         for electrophotography                                                        Acceptance potential                                                                       ±10 V     ±30 V                                            irregularity in                                                               circumferential direction                                                     Acceptance potential                                                                       ±15 V     ±36 V                                            irregularity in axial                                                         direction                                                                     Remarks      Example according to the                                                                   Example according to plasma                                      process of this invention                                                                  CVD of the prior art                                                          Substrate temperature 250°                   __________________________________________________________________________                              C.                                              

                                      TABLE 3F                                    __________________________________________________________________________                 Example 56                                                                          Example 57                                                                          Example 58                                                                          Example 59                                     __________________________________________________________________________    Starting gas for formation                                                                 N.sub.2                                                                             NO    N.sub.2 O                                                                           N.sub.2 O.sub.4                                of active species (B)                                                         Rectifying ratio of                                                                        4.2 × 10.sup.2                                                                4.8 × 10.sup.2                                                                5.7 × 10.sup.2                                                                9.0 × 10.sup.2                           diode (*1)                                                                    η value of diode (*2)                                                                  1.2   1.3   1.4   1.1                                            __________________________________________________________________________     (*1) Ratio of forward current to reverse current at voltage 1 V               (*2) η value (Quality Factor) in the current formula of p - n             junction:                                                                     ##STR6##                                                                 

What is claimed is:
 1. A process for forming a deposited film, whichcomprises introducing into a film forming space housing a substratetherein an active species (A) formed by decomposition of a compoundcontaining germanium and a halogen and an active species (B) formed froma chemical substance for film formation which is reactive with saidactive species (A) separately from each other, then irradiating themwith light energy and thereby allowing both the species to react witheach other thereby to form a deposited film on the substrate.
 2. Aprocess according to claim 1, wherein said active species (B) is formedfrom hydrogen and/or a halogen compound.
 3. A process according to claim1, wherein said active species (B) is formed from a silicon containingcompound.
 4. A process according to claim 1, wherein said active species(B) is formed from a carbon containing compound.
 5. A process accordingto claim 1, wherein said active species (B) is formed from a germaniumcontaining compound.
 6. A process according to claim 1, wherein saidactive species (B) is formed from an oxygen containing compound.
 7. Aprocess according to claim 1, wherein said active species (B) is formedfrom a nitrogen containing compound.
 8. A process according to claim 1,wherein said active species (A) is formed by decomposition of a chain orcyclic hydrogenated germanium of which hydrogen atoms are partially orwholly substituted with halogen atoms.
 9. A process according to claim8, wherein said active species (B) is formed from hydrogen and/or ahalogen compound.
 10. A process according to claim 8, wherein saidactive species (B) is formed from a silicon containing compound.
 11. Aprocess according to claim 8, wherein said active species (B) is formedfrom a carbon containing compound.
 12. A process according to claim 8,wherein said active apecies (B) is formed from a germanium containingcompound.
 13. A process according to claim 8, wherein said activespecies (B) is formed from an oxygen containing compound.
 14. A processaccording to claim 8, wherein said active species (B) is formed from anitorgen containing compound.
 15. A process according to claim 1,wherein an active species (SX) formed by decomposition of a compoundcontaining silicon and a halogen and/or an active species (CX) formed bydecomposition of a compound containing carbon and a halogen is used inaddition to said active species (A).
 16. A process according to claim15, wherein said active species (B) is formed from hydrogen and/or ahalogen compound.
 17. A process according to claim 15, wherein saidactive species (B) is formed from a silicon containing compound.
 18. Aprocess according to claim 15, wherein said active species (B) is formedfrom a carbon containing compound.
 19. A process according to claim 15,wherein said active species (B) is formed from a germanium containingcompound.
 20. A process according to claim 15, wherein said activespecies (B) is formed from an oxygen containing compound.
 21. A processaccording to claim 15, wherein said active species (B) is formed from anitrogen containing compound.
 22. A process according to claim 1,wherein the proportion in amount of said active species (A) to saidactive species (B) introduced into the film forming space is 10:1 to1:10.
 23. A process according to claim 1, wherein the life of saidactive species (A) is 0.1 second or longer.